Comment puis-je faire quelque chose comme un FlowLayoutsous Android?
Réponses:
Si vous regardez le discours que j'ai donné lors de la journée de l'Université Devoxx (disponible sur parleys.com ), vous apprendrez à le faire vous-même. Pendant la conférence, j'ai écrit une FlowLayoutimplémentation en direct sur scène pour montrer à quel point il est simple d'écrire des mises en page personnalisées.
L'implémentation est hébergée ici .
Vous devez utiliser FlexboxLayoutavec flexWrap="wrap"attribut.
<com.google.android.flexbox.FlexboxLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:flexWrap="wrap">
<!-- contents go here -->
</com.google.android.flexbox.FlexboxLayout>
Pour obtenir des instructions de compilation, consultez le dépôt github.
En savoir plus à ce sujet - https://android-developers.googleblog.com/2017/02/build-flexible-layouts-with.html
Je n'ai pas assez de réputation pour publier un commentaire sur la réponse de Romain Guy mais c'est là que devrait se trouver cette réponse (j'ai créé un compte juste pour partager ma modification).
Quoi qu'il en soit, je vois que d'autres personnes ont découvert que sa solution FlowLayout plutôt cool avait quelques problèmes. J'ai pu en trouver un moi-même et j'ai vu, comme d'autres, que certains enfants étaient coupés. En regardant en détail l'algorithme, cela semble être une erreur très simple dans le calcul de la hauteur. Lorsque le tout dernier enfant est celui qui est placé sur une nouvelle ligne, alors la hauteur n'a pas été correctement calculée. J'ai nettoyé un peu le calcul (il y avait une utilisation étrange de "height" par rapport à currentHeight).
La modification suivante résout le problème du «dernier enfant est coupé s'il est sur une nouvelle ligne»:
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
int widthLimit = MeasureSpec.getSize(widthMeasureSpec) - getPaddingRight();
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
boolean growHeight = widthMode != MeasureSpec.UNSPECIFIED;
int width = 0;
int currentWidth = getPaddingLeft();
int currentHeight = getPaddingTop();
int maxChildHeight = 0;
boolean breakLine = false;
boolean newLine = false;
int spacing = 0;
final int count = getChildCount();
for (int i = 0; i < count; i++)
{
View child = getChildAt(i);
measureChild(child, widthMeasureSpec, heightMeasureSpec);
LayoutParams lp = (LayoutParams) child.getLayoutParams();
spacing = mHorizontalSpacing;
if (lp.horizontalSpacing >= 0)
{
spacing = lp.horizontalSpacing;
}
if (growHeight && (breakLine || ((currentWidth + child.getMeasuredWidth()) > widthLimit)))
{
newLine = true;
currentHeight += maxChildHeight + mVerticalSpacing;
width = Math.max(width, currentWidth - spacing);
currentWidth = getPaddingLeft();
maxChildHeight = 0;
}
else
{
newLine = false;
}
maxChildHeight = Math.max(maxChildHeight, child.getMeasuredHeight());
lp.x = currentWidth;
lp.y = currentHeight;
currentWidth += child.getMeasuredWidth() + spacing;
breakLine = lp.breakLine;
}
if (newLine == false)
{
width = Math.max(width, currentWidth - spacing);
}
width += getPaddingRight();
int height = currentHeight + maxChildHeight + getPaddingBottom();
setMeasuredDimension(resolveSize(width, widthMeasureSpec),
resolveSize(height, heightMeasureSpec));
}
Il existe une bibliothèque de Google, appelée "flexbox-layout" . Tu devrais y jeter un coup d'oeil.
Pour l'utiliser dans RecyclerView, vous pouvez utiliser quelque chose comme ça:
val layoutManager = FlexboxLayoutManager(activity)
layoutManager.flexDirection = FlexDirection.ROW
layoutManager.flexWrap = FlexWrap.WRAP
layoutManager.justifyContent = JustifyContent.FLEX_START
layoutManager.alignItems = AlignItems.FLEX_START
recyclerView.layoutManager=layoutManager
Comme l'une des réponses précédentes, j'ai commencé avec la solution ici: http://hzqtc.github.io/2013/12/android-custom-layout-flowlayout.html
Je l'ai étendu pour tenir compte des différentes hauteurs d'enfants comme ci-dessous.
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
// Custom layout that wraps child views to a new line
public class FlowLayout extends ViewGroup {
private int marginHorizontal;
private int marginVertical;
public FlowLayout(Context context) {
super(context);
init();
}
public FlowLayout(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public FlowLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() { // Specify the margins for the children
marginHorizontal = getResources().getDimensionPixelSize(R.dimen.activity_half_horizontal_margin);
marginVertical = getResources().getDimensionPixelSize(R.dimen.activity_half_vertical_margin);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int childLeft = getPaddingLeft();
int childTop = getPaddingTop();
int lowestBottom = 0;
int lineHeight = 0;
int myWidth = resolveSize(100, widthMeasureSpec);
int wantedHeight = 0;
for (int i = 0; i < getChildCount(); i++) {
final View child = getChildAt(i);
if (child.getVisibility() == View.GONE) {
continue;
}
child.measure(getChildMeasureSpec(widthMeasureSpec, 0, child.getLayoutParams().width),
getChildMeasureSpec(heightMeasureSpec, 0, child.getLayoutParams().height));
int childWidth = child.getMeasuredWidth();
int childHeight = child.getMeasuredHeight();
lineHeight = Math.max(childHeight, lineHeight);
if (childWidth + childLeft + getPaddingRight() > myWidth) { // Wrap this line
childLeft = getPaddingLeft();
childTop = marginVertical + lowestBottom; // Spaced below the previous lowest point
lineHeight = childHeight;
}
childLeft += childWidth + marginHorizontal;
if (childHeight + childTop > lowestBottom) { // New lowest point
lowestBottom = childHeight + childTop;
}
}
wantedHeight += childTop + lineHeight + getPaddingBottom();
setMeasuredDimension(myWidth, resolveSize(wantedHeight, heightMeasureSpec));
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
int childLeft = getPaddingLeft();
int childTop = getPaddingTop();
int lowestBottom = 0;
int myWidth = right - left;
for (int i = 0; i < getChildCount(); i++) {
final View child = getChildAt(i);
if (child.getVisibility() == View.GONE) {
continue;
}
int childWidth = child.getMeasuredWidth();
int childHeight = child.getMeasuredHeight();
if (childWidth + childLeft + getPaddingRight() > myWidth) { // Wrap this line
childLeft = getPaddingLeft();
childTop = marginVertical + lowestBottom; // Spaced below the previous lowest point
}
child.layout(childLeft, childTop, childLeft + childWidth, childTop + childHeight);
childLeft += childWidth + marginHorizontal;
if (childHeight + childTop > lowestBottom) { // New lowest point
lowestBottom = childHeight + childTop;
}
}
}
}
J'ai utilisé cela comme une solution pour envelopper TextEdits multilignes. J'espère que ça aide!
Voici la classe personnalisée où vous pouvez obtenir une mise en page comme suit avec l'ajout d'une vue dynamique (également appelée FlowLayout).
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
/*
Created By Dhavalkumar Solanki
* */
public class FlowLayout extends ViewGroup {
private int line_height_space;
public static class LayoutParams extends ViewGroup.LayoutParams {
public int horizontal_spacing;
public int vertical_spacing;
/**
* @param horizontal_spacing Pixels between items, horizontally
* @param vertical_spacing Pixels between items, vertically
*/
public LayoutParams(int horizontal_spacing, int vertical_spacing) {
super(0, 0);
this.horizontal_spacing = horizontal_spacing;
this.vertical_spacing = vertical_spacing;
}
}
public FlowLayout(Context context) {
super(context);
}
public FlowLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
assert (MeasureSpec.getMode(widthMeasureSpec) != MeasureSpec.UNSPECIFIED);
final int width = MeasureSpec.getSize(widthMeasureSpec) - getPaddingLeft() - getPaddingRight();
int height = MeasureSpec.getSize(heightMeasureSpec) - getPaddingTop() - getPaddingBottom();
final int count = getChildCount();
int line_height_space = 0;
int xpos = getPaddingLeft();
int ypos = getPaddingTop();
int childHeightMeasureSpec;
if (MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.AT_MOST) {
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.AT_MOST);
} else {
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
}
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() != GONE) {
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
child.measure(MeasureSpec.makeMeasureSpec(width, MeasureSpec.AT_MOST), childHeightMeasureSpec);
final int childw = child.getMeasuredWidth();
line_height_space = Math.max(line_height_space, child.getMeasuredHeight() + lp.vertical_spacing);
if (xpos + childw > width) {
xpos = getPaddingLeft();
ypos += line_height_space;
}
xpos += childw + lp.horizontal_spacing;
}
}
this.line_height_space = line_height_space;
if (MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.UNSPECIFIED) {
height = ypos + line_height_space;
} else if (MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.AT_MOST) {
if (ypos + line_height_space < height) {
height = ypos + line_height_space;
}
}
setMeasuredDimension(width, height);
}
@Override
protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
return new LayoutParams(1, 1); // default of 1px spacing
}
@Override
protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
if (p instanceof LayoutParams) {
return true;
}
return false;
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
final int count = getChildCount();
final int width = r - l;
int xpos = getPaddingLeft();
int ypos = getPaddingTop();
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() != GONE) {
final int childw = child.getMeasuredWidth();
final int childh = child.getMeasuredHeight();
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
if (xpos + childw > width) {
xpos = getPaddingLeft();
ypos += line_height_space;
}
child.layout(xpos, ypos, xpos + childw, ypos + childh);
xpos += childw + lp.horizontal_spacing;
}
}
}
}
Exemple :
text_view.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tool="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="5dp">
<TextView
android:id="@+id/tvText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="19sp"
android:background="@drawable/unselected_tag"
android:textColor="@color/colorPrimary"
tool:text="Temp" />
</RelativeLayout>
activity_flow_layou_demo.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/tvTitleBusiness"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Business Interest "
android:textColor="@color/colorPrimary"
android:textSize="25sp" />
<com.example.tristateandroid2.radardemo.FlowLayout
android:id="@+id/flowBusiness"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</com.example.tristateandroid2.radardemo.FlowLayout>
</LinearLayout>
<LinearLayout
android:layout_marginTop="@dimen/activity_horizontal_margin"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/tvTitlePrivate"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Private Interest "
android:textColor="@color/colorPrimary"
android:textSize="25sp" />
<com.example.tristateandroid2.radardemo.FlowLayout
android:id="@+id/flowPrivate"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</com.example.tristateandroid2.radardemo.FlowLayout>
</LinearLayout>
</LinearLayout>
</ScrollView>
</RelativeLayout>
FlowLayouDemo.java
import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView;
import java.util.ArrayList;
public class FlowLayouDemo extends AppCompatActivity {
private TextView tvTitleBusiness;
private FlowLayout flowBusiness;
private TextView tvTitlePrivate;
private FlowLayout flowPrivate;
private ArrayList<TagModel> arrayList;
private void findViews() {
tvTitleBusiness = (TextView) findViewById(R.id.tvTitleBusiness);
flowBusiness = (FlowLayout) findViewById(R.id.flowBusiness);
tvTitlePrivate = (TextView) findViewById(R.id.tvTitlePrivate);
flowPrivate = (FlowLayout) findViewById(R.id.flowPrivate);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_flow_layou_demo);
findViews();
addLayouts();
}
private void addLayouts() {
if (arrayList == null) {
arrayList = new ArrayList<>();
}
flowBusiness.removeAllViews();
flowPrivate.removeAllViews();
for (int i = 0; i < 75; i++) {
final boolean[] selected = {false};
View view = this.getLayoutInflater().inflate(R.layout.text_view, null);
final TextView textView = (TextView) view.findViewById(R.id.tvText);
if (i % 5 == 0) {
arrayList.add(new TagModel(i, false, "Business VIEW : " + i));
textView.setText("Busi VIEW To IS : " + i);
} else {
arrayList.add(new TagModel(i, false, "TEXT IS : " + i));
textView.setText("Busi IS : " + i);
}
textView.setBackgroundResource(R.drawable.unselected_tag);
textView.setTextColor(Color.parseColor("#3F51B5"));
textView.setTag(i);
if(i<=50){
flowBusiness.addView(view);
}else {
textView.setText("Priv View : "+i);
flowPrivate.addView(view);
}
textView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (selected[0]) {
selected[0] = false;
textView.setBackgroundResource(R.drawable.unselected_tag);
textView.setTextColor(Color.parseColor("#3F51B5"));
} else {
selected[0] = true;
textView.setBackgroundResource(R.drawable.selected_tag);
textView.setTextColor(Color.parseColor("#FFFFFF"));
}
}
});
}
}
}
Une révision de @MattNotEquals () FlowLayout qui prend en charge MarginLayoutParams.
Il s'agit simplement d'une implémentation minimaliste de MarginLayoutParms pour prendre en charge les marges gauche, droite, supérieure et inférieure.
import android.content.Context;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
/**
* Original version courtesy of MattNotEquals() at http://stackoverflow.com/a/34169798/4515489 - 4/13/17.
* 7/15/17 Revised to support MarginLayoutParams.
*/
public class FlowLayout extends ViewGroup {
// Custom layout that wraps child views to a new line.
public FlowLayout(Context context) {
super(context);
}
public FlowLayout(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public FlowLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int childLeft = getPaddingLeft();
int childTop = getPaddingTop();
int lowestBottom = 0;
int lineHeight = 0;
int myWidth = resolveSize(100, widthMeasureSpec);
int wantedHeight = 0;
for (int i = 0; i < getChildCount(); i++) {
final View child = getChildAt(i);
if (child.getVisibility() == View.GONE) {
continue;
}
child.measure(getChildMeasureSpec(widthMeasureSpec, 0, child.getLayoutParams().width),
getChildMeasureSpec(heightMeasureSpec, 0, child.getLayoutParams().height));
int childWidth = child.getMeasuredWidth();
int childHeight = child.getMeasuredHeight();
lineHeight = Math.max(childHeight, lineHeight);
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
childLeft += lp.leftMargin;
childTop += lp.topMargin;
if (childLeft + childWidth + lp.rightMargin + getPaddingRight() > myWidth) { // Wrap this line
childLeft = getPaddingLeft() + lp.leftMargin;
childTop = lowestBottom + lp.topMargin; // Spaced below the previous lowest point
lineHeight = childHeight;
}
childLeft += childWidth + lp.rightMargin;
if (childTop + childHeight + lp.bottomMargin > lowestBottom) { // New lowest point
lowestBottom = childTop + childHeight + lp.bottomMargin;
}
}
wantedHeight += lowestBottom + getPaddingBottom(); // childTop + lineHeight + getPaddingBottom();
setMeasuredDimension(myWidth, resolveSize(wantedHeight, heightMeasureSpec));
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
int childLeft = getPaddingLeft();
int childTop = getPaddingTop();
int lowestBottom = 0;
int myWidth = right - left;
for (int i = 0; i < getChildCount(); i++) {
final View child = getChildAt(i);
if (child.getVisibility() == View.GONE) {
continue;
}
int childWidth = child.getMeasuredWidth();
int childHeight = child.getMeasuredHeight();
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
childLeft += lp.leftMargin;
childTop += lp.topMargin;
if (childLeft + childWidth + lp.rightMargin + getPaddingRight() > myWidth) { // Wrap this line
childLeft = getPaddingLeft() + lp.leftMargin;
childTop = lowestBottom + lp.topMargin; // Spaced below the previous lowest point
}
child.layout(childLeft, childTop, childLeft + childWidth, childTop + childHeight);
childLeft += childWidth + lp.rightMargin;
if (childTop + childHeight + lp.bottomMargin > lowestBottom) { // New lowest point
lowestBottom = childTop + childHeight + lp.bottomMargin;
}
}
}
@Override
public boolean shouldDelayChildPressedState() {
return false;
}
@Override
protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
return p instanceof LayoutParams;
}
@Override
protected LayoutParams generateDefaultLayoutParams() {
return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
}
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new FlowLayout.LayoutParams(getContext(), attrs);
}
@Override
protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) {
if (lp instanceof LayoutParams) {
return new LayoutParams((LayoutParams) lp);
}
else if (lp instanceof MarginLayoutParams) {
return new LayoutParams((MarginLayoutParams) lp);
}
else
return super.generateLayoutParams(lp);
}
/**
* Per-child layout information for layouts that support margins.
*/
public static class LayoutParams extends MarginLayoutParams {
public LayoutParams(@NonNull Context c, @Nullable AttributeSet attrs) {
super(c, attrs);
}
public LayoutParams(int width, int height) {
super(width, height);
}
public LayoutParams(@NonNull ViewGroup.LayoutParams source) {
super(source);
}
public LayoutParams(@NonNull ViewGroup.MarginLayoutParams source) {
super(source);
}
public LayoutParams(@NonNull LayoutParams source) {
super(source);
}
}
}
android:layout_margin="10dp"dans le fichier de mise en page, ou définir des marges individuelles avec des attributs tels que android:layout_marginLeft="10dp", android:layout_marginTop="4dp", ..etc.
Beau code FlowLayout autonome simple ici (juste quelques fichiers concis gist.github) :
http://hzqtc.github.io/2013/12/android-custom-layout-flowlayout.html
Cependant, l'activité prête à l'emploi ne m'a pas permis de charger la mise en page personnalisée.
J'ai trouvé cette solution de contournement [en utilisant l'appel 2-param .inflate () de cet exemple ] :
@Override
protected void onCreate(Bundle savedInstanceState)
{
// ..
setContentView(R.layout.main_res_layout_activity_main);
ViewGroup flowContainer = getFlowLayoutView();
// ..
}
ViewGroup getFlowLayoutView()
{
LayoutInflater inflater = getLayoutInflater();
ViewGroup flowLayout =
(ViewGroup)
inflater.inflate(
R.layout.main_res_layout_activity_main,
(FlowLayout) findViewById(R.id.flow_container)
);
return flowLayout;
}
Il existe maintenant une prise en charge intégrée dans ConstraintLayout à l'aide d'un widget Flow. Il dispose de nombreuses options qui peuvent être utilisées pour réaliser de nombreux types de flux.
Exemple:
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.constraintlayout.helper.widget.Flow
android:layout_width="0dp"
android:layout_height="wrap_content"
app:constraint_referenced_ids="item_1,item_2,item_3"
app:flow_horizontalBias="0"
app:flow_horizontalGap="10dp"
app:flow_horizontalStyle="packed"
app:flow_verticalGap="8dp"
app:flow_wrapMode="aligned"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<View
android:id="@+id/item_1"
android:layout_width="50dp"
android:layout_height="50dp" />
<View
android:id="@+id/item_2"
android:layout_width="50dp"
android:layout_height="50dp" />
<View
android:id="@+id/item_3"
android:layout_width="50dp"
android:layout_height="50dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
Jetez un œil à cet article: https://medium.com/@tapanrgohil/constraintlayout-flow-bye-bye-to-linerlayout-78fd7fa9b679
Et ici: https://www.bignerdranch.com/blog/constraintlayout-flow-simple-grid-building-without-nested-layouts/