如何使用支持库实现波纹动画？

Question

我正在尝试在按钮单击时添加波纹动画。我确实喜欢下面，但它需要 minSdKVersion 到 21。

ripple.xml

<ripple xmlns:android="http://schemas.android.com/apk/res/android"
    android:color="?android:colorControlHighlight">
    <item>
        <shape android:shape="rectangle">
            <solid android:color="?android:colorAccent" />
        </shape>
    </item>
</ripple>

按钮

<com.devspark.robototextview.widget.RobotoButton
    android:id="@+id/loginButton"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/ripple"
    android:text="@string/login_button" />

我想让它向后兼容设计库。

如何做到这一点？

Answer 1

基本波纹设置

• 视图中包含的涟漪。
  android:background="?selectableItemBackground"

• 超出视图边界的涟漪：
  android:background="?selectableItemBackgroundBorderless"

  查看 here 以解析 Java 代码中的 ?(attr) xml 引用。

支持库

• 使用?attr:（或? 简写）而不是?android:attr 引用support library，因此可返回到API 7。

带有图像/背景的涟漪

• 要拥有图像或背景并叠加波纹，最简单的解决方案是将View 包裹在FrameLayout 中，波纹设置为setForeground() 或setBackground()。

老实说，否则没有干净的方法可以做到这一点。

Answer 2

我以前投票关闭这个问题作为离题，但实际上我改变了主意，因为这是非常好的视觉效果，不幸的是，它还不是支持库的一部分。它很可能会出现在未来的更新中，但没有公布时间框架。

幸运的是，已经有一些自定义实现可用：

• https://github.com/traex/RippleEffect
• https://github.com/balysv/material-ripple
• https://github.com/siriscac/RippleView
• https://github.com/ozodrukh/RippleDrawable

包括与旧版本 Android 兼容的 Material 主题小部件集：

• https://github.com/keithellis/MaterialWidget

所以您可以尝试其中一种或谷歌搜索其他“材料小部件”……

Answer 3

我做了一个简单的类来制作波纹按钮，我最终不需要它，所以它不是最好的，但它是：

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.Button;

public class RippleView extends Button
{
    private float duration = 250;

    private float speed = 1;
    private float radius = 0;
    private Paint paint = new Paint();
    private float endRadius = 0;
    private float rippleX = 0;
    private float rippleY = 0;
    private int width = 0;
    private int height = 0;
    private OnClickListener clickListener = null;
    private Handler handler;
    private int touchAction;
    private RippleView thisRippleView = this;

    public RippleView(Context context)
    {
        this(context, null, 0);
    }

    public RippleView(Context context, AttributeSet attrs)
    {
        this(context, attrs, 0);
    }

    public RippleView(Context context, AttributeSet attrs, int defStyleAttr)
    {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init()
    {
        if (isInEditMode())
            return;

        handler = new Handler();
        paint.setStyle(Paint.Style.FILL);
        paint.setColor(Color.WHITE);
        paint.setAntiAlias(true);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh)
    {
        super.onSizeChanged(w, h, oldw, oldh);
        width = w;
        height = h;
    }

    @Override
    protected void onDraw(@NonNull Canvas canvas)
    {
        super.onDraw(canvas);

        if(radius > 0 && radius < endRadius)
        {
            canvas.drawCircle(rippleX, rippleY, radius, paint);
            if(touchAction == MotionEvent.ACTION_UP)
                invalidate();
        }
    }

    @Override
    public boolean onTouchEvent(@NonNull MotionEvent event)
    {
        rippleX = event.getX();
        rippleY = event.getY();

        switch(event.getAction())
        {
            case MotionEvent.ACTION_UP:
            {
                getParent().requestDisallowInterceptTouchEvent(false);
                touchAction = MotionEvent.ACTION_UP;

                radius = 1;
                endRadius = Math.max(Math.max(Math.max(width - rippleX, rippleX), rippleY), height - rippleY);
                speed = endRadius / duration * 10;
                handler.postDelayed(new Runnable()
                {
                    @Override
                    public void run()
                    {
                        if(radius < endRadius)
                        {
                            radius += speed;
                            paint.setAlpha(90 - (int) (radius / endRadius * 90));
                            handler.postDelayed(this, 1);
                        }
                        else
                        {
                            clickListener.onClick(thisRippleView);
                        }
                    }
                }, 10);
                invalidate();
                break;
            }
            case MotionEvent.ACTION_CANCEL:
            {
                getParent().requestDisallowInterceptTouchEvent(false);
                touchAction = MotionEvent.ACTION_CANCEL;
                radius = 0;
                invalidate();
                break;
            }
            case MotionEvent.ACTION_DOWN:
            {
                getParent().requestDisallowInterceptTouchEvent(true);
                touchAction = MotionEvent.ACTION_UP;
                endRadius = Math.max(Math.max(Math.max(width - rippleX, rippleX), rippleY), height - rippleY);
                paint.setAlpha(90);
                radius = endRadius/4;
                invalidate();
                return true;
            }
            case MotionEvent.ACTION_MOVE:
            {
                if(rippleX < 0 || rippleX > width || rippleY < 0 || rippleY > height)
                {
                    getParent().requestDisallowInterceptTouchEvent(false);
                    touchAction = MotionEvent.ACTION_CANCEL;
                    radius = 0;
                    invalidate();
                    break;
                }
                else
                {
                    touchAction = MotionEvent.ACTION_MOVE;
                    invalidate();
                    return true;
                }
            }
        }

        return false;
    }

    @Override
    public void setOnClickListener(OnClickListener l)
    {
        clickListener = l;
    }
}

编辑

因为很多人都在寻找这样的东西，所以我创建了一个可以让其他视图产生连锁反应的类：

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;

public class RippleViewCreator extends FrameLayout
{
    private float duration = 150;
    private int frameRate = 15;

    private float speed = 1;
    private float radius = 0;
    private Paint paint = new Paint();
    private float endRadius = 0;
    private float rippleX = 0;
    private float rippleY = 0;
    private int width = 0;
    private int height = 0;
    private Handler handler = new Handler();
    private int touchAction;

    public RippleViewCreator(Context context)
    {
        this(context, null, 0);
    }

    public RippleViewCreator(Context context, AttributeSet attrs)
    {
        this(context, attrs, 0);
    }

    public RippleViewCreator(Context context, AttributeSet attrs, int defStyleAttr)
    {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init()
    {
        if (isInEditMode())
            return;

        paint.setStyle(Paint.Style.FILL);
        paint.setColor(getResources().getColor(R.color.control_highlight_color));
        paint.setAntiAlias(true);

        setWillNotDraw(true);
        setDrawingCacheEnabled(true);
        setClickable(true);
    }

    public static void addRippleToView(View v)
    {
        ViewGroup parent = (ViewGroup)v.getParent();
        int index = -1;
        if(parent != null)
        {
            index = parent.indexOfChild(v);
            parent.removeView(v);
        }
        RippleViewCreator rippleViewCreator = new RippleViewCreator(v.getContext());
        rippleViewCreator.setLayoutParams(v.getLayoutParams());
        if(index == -1)
            parent.addView(rippleViewCreator, index);
        else
            parent.addView(rippleViewCreator);
        rippleViewCreator.addView(v);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh)
    {
        super.onSizeChanged(w, h, oldw, oldh);
        width = w;
        height = h;
    }

    @Override
    protected void dispatchDraw(@NonNull Canvas canvas)
    {
        super.dispatchDraw(canvas);

        if(radius > 0 && radius < endRadius)
        {
            canvas.drawCircle(rippleX, rippleY, radius, paint);
            if(touchAction == MotionEvent.ACTION_UP)
                invalidate();
        }
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event)
    {
        return true;
    }

    @Override
    public boolean onTouchEvent(@NonNull MotionEvent event)
    {
        rippleX = event.getX();
        rippleY = event.getY();

        touchAction = event.getAction();
        switch(event.getAction())
        {
            case MotionEvent.ACTION_UP:
            {
                getParent().requestDisallowInterceptTouchEvent(false);

                radius = 1;
                endRadius = Math.max(Math.max(Math.max(width - rippleX, rippleX), rippleY), height - rippleY);
                speed = endRadius / duration * frameRate;
                handler.postDelayed(new Runnable()
                {
                    @Override
                    public void run()
                    {
                        if(radius < endRadius)
                        {
                            radius += speed;
                            paint.setAlpha(90 - (int) (radius / endRadius * 90));
                            handler.postDelayed(this, frameRate);
                        }
                        else if(getChildAt(0) != null)
                        {
                            getChildAt(0).performClick();
                        }
                    }
                }, frameRate);
                break;
            }
            case MotionEvent.ACTION_CANCEL:
            {
                getParent().requestDisallowInterceptTouchEvent(false);
                break;
            }
            case MotionEvent.ACTION_DOWN:
            {
                getParent().requestDisallowInterceptTouchEvent(true);
                endRadius = Math.max(Math.max(Math.max(width - rippleX, rippleX), rippleY), height - rippleY);
                paint.setAlpha(90);
                radius = endRadius/3;
                invalidate();
                return true;
            }
            case MotionEvent.ACTION_MOVE:
            {
                if(rippleX < 0 || rippleX > width || rippleY < 0 || rippleY > height)
                {
                    getParent().requestDisallowInterceptTouchEvent(false);
                    touchAction = MotionEvent.ACTION_CANCEL;
                    break;
                }
                else
                {
                    invalidate();
                    return true;
                }
            }
        }
        invalidate();
        return false;
    }

    @Override
    public final void addView(@NonNull View child, int index, ViewGroup.LayoutParams params)
    {
        //limit one view
        if (getChildCount() > 0)
        {
            throw new IllegalStateException(this.getClass().toString()+" can only have one child.");
        }
        super.addView(child, index, params);
    }
}

Answer 4

这很简单;-)

首先您必须创建两个可绘制文件，一个用于旧 api 版本，另一个用于最新版本，当然！如果您为最新的 api 版本 android studio 创建可绘制文件，建议您自动创建旧的。最后将此drawable设置为您的背景视图。

新 api 版本的可绘制示例 (res/drawable-v21/ripple.xml)：

<?xml version="1.0" encoding="utf-8"?>
<ripple xmlns:android="http://schemas.android.com/apk/res/android"
    android:color="?android:colorControlHighlight">
    <item>
        <shape android:shape="rectangle">
            <solid android:color="@color/colorPrimary" />
            <corners android:radius="@dimen/round_corner" />
        </shape>
    </item>
</ripple>

旧 api 版本的可绘制示例 (res/drawable/ripple.xml)

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="@color/colorPrimary" />
    <corners android:radius="@dimen/round_corner" />
</shape>

有关ripple drawable的更多信息，请访问：https://developer.android.com/reference/android/graphics/drawable/RippleDrawable.html

Answer 5

有时您有自定义背景，在这种情况下，更好的解决方案是使用android:foreground="?selectableItemBackground"

更新

如果你想要带有圆角和自定义背景的波纹效果，你可以使用这个：

background_ripple.xml

<?xml version="1.0" encoding="utf-8"?>
<ripple xmlns:android="http://schemas.android.com/apk/res/android" android:color="@color/ripple_color">
<item android:id="@android:id/mask">
    <shape android:shape="rectangle">
        <solid android:color="@android:color/white" />
        <corners android:radius="5dp" />
    </shape>
</item>

<item android:id="@android:id/background">
    <shape android:shape="rectangle">
        <solid android:color="@android:color/white" />
        <corners android:radius="5dp" />
    </shape>
</item>

layout.xml

<Button
    android:id="@+id/btn_play"
    android:background="@drawable/background_ripple"
    app:backgroundTint="@color/colorPrimary"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="@string/play_now" />

我在 API >= 21 上使用过这个

Answer 6

有时这条线可以用于任何布局或组件。

 android:background="?attr/selectableItemBackground"

喜欢。

 <RelativeLayout
                android:id="@+id/relative_ticket_checkin"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:background="?attr/selectableItemBackground">