android:tint

Tint Drawable Resources
With Android 5.0 (API level 21) and above, you can tint bitmaps and nine-patches defined as alpha masks. You can tint them with color resources or theme attributes that resolve to color resources (for example, ?android:attr/colorPrimary). Usually, you create these assets only once and color them automatically to match your theme.

You can apply a tint to BitmapDrawable or NinePatchDrawable objects with the setTint() method. You can also set the tint color and mode in your layouts with the android:tint and android:tintMode attributes.

Drawable 的染色，遮罩或者绘制。 在5.0以后我们就可以为bitmap或者是9-patch定义一个透明的遮罩。
BitmapDrawable 和NinePatchDrawable使用setTint()方法.(是drawable的方法不是控件的)
而在xml文件中使用android:tint和android:tintMode这两个属性。

注意点： 使用android:tint指定颜色时一定要带透明度。#50ff00ff也就是说是8位的色值而不是6位的。

属性说明：
android:tint： 设置的是颜色
android:tintMode：设置的是类型(src_in,src_over,src_atop,add,screen,multiply)
类型说明：
src_in 只显示设置的遮罩颜色。 相当于遮罩在里面。
src_over遮罩颜色和图片都显示。相当于遮罩在图片上方。(特别是色值带透明度的)
src_atop遮罩在图片上方
multiply 混合色遮罩
screen
add 混合遮罩，drawable颜色和透明度。

官网说明：
src_over:   3    
The tint is drawn on top of the drawable. [Sa + (1 - Sa)*Da, Rc = Sc + (1 - Sa)*Dc]

src_in: 5    
The tint is masked by the alpha channel of the drawable. The drawable’s color channels are thrown out. [Sa * Da, Sc * Da]

src_atop:   9    
The tint is drawn above the drawable, but with the drawable’s alpha channel masking the result. [Da, Sc * Da + (1 - Sa) * Dc]

multiply:   14   
Multiplies the color and alpha channels of the drawable with those of the tint. [Sa * Da, Sc * Dc]

screen: 15   
[Sa + Da - Sa * Da, Sc + Dc - Sc * Dc]

add:    16   
Combines the tint and drawable color and alpha channels, clamping the result to valid color values. Saturate(S + D)

代码设置：
1，ImageView
mImage.setColorFilter(mHintColor, mMode);
2，Button，TextView等
tv.setBackgroundTintList(ColorStateList.valueOf(Color.parseColor(“#ff00ff”)));
tv.setBackgroundTintMode(Mode.SRC_OVER);

xml布局文件： 原图和设置tint后的对比。

 <ImageView
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:scaleType="centerCrop"
            android:src="@drawable/zly1" />

        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:scaleType="centerCrop"
            android:src="@drawable/zly1"
            android:tint="#90ff00ff"
            android:tintMode="multiply" />

        <TextView
            android:id="@+id/textView1"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:layout_gravity="center_vertical"
            android:layout_marginLeft="10dip"
            android:background="@drawable/zly1"
            android:backgroundTint="#90ff00ff"
            android:backgroundTintMode="multiply"
            android:text="tint_tintMode"
            android:textColor="#00ffff" />

效果图：
src_over效果

multiply效果

这几个属性感觉和xfremode非常相似：

private static final Xfermode[] sModes = {
            new PorterDuffXfermode(PorterDuff.Mode.CLEAR),
            new PorterDuffXfermode(PorterDuff.Mode.SRC),
            new PorterDuffXfermode(PorterDuff.Mode.DST),
            new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER),
            new PorterDuffXfermode(PorterDuff.Mode.DST_OVER),
            new PorterDuffXfermode(PorterDuff.Mode.SRC_IN),
            new PorterDuffXfermode(PorterDuff.Mode.DST_IN),
            new PorterDuffXfermode(PorterDuff.Mode.SRC_OUT),
            new PorterDuffXfermode(PorterDuff.Mode.DST_OUT),
            new PorterDuffXfermode(PorterDuff.Mode.SRC_ATOP),
            new PorterDuffXfermode(PorterDuff.Mode.DST_ATOP),
            new PorterDuffXfermode(PorterDuff.Mode.XOR),
            new PorterDuffXfermode(PorterDuff.Mode.DARKEN),
            new PorterDuffXfermode(PorterDuff.Mode.LIGHTEN),
            new PorterDuffXfermode(PorterDuff.Mode.MULTIPLY),
            new PorterDuffXfermode(PorterDuff.Mode.SCREEN)
        };

对应的效果图：