介绍三种方案全局设置灰白模式,原理都是相同的,利用Android提供的ColorMatrix(颜色矩阵),将其饱和度设置为0,这样使用Paint绘制出来的都是没有饱和度的灰白样式!
不同的方案只是设置时机不同而已。
Android APP全局黑白化实现方案_xiaoerbuyu1233的博客-CSDN博客
最简单方案:监控activity生命周期,在onCreate中置灰
Application里面不是有registerActivityLifecycleCallbacks这个注册监听方法吗?监听里面的onActivityCreated不是可以获取到当前的Activity吗?那DecorView不就拿到了!
public class StudyApp extends Application {
@Override
public void onCreate() {
super.onCreate();
Paint mPaint = new Paint();
ColorMatrix mColorMatrix = new ColorMatrix();
mColorMatrix.setSaturation(0);
mPaint.setColorFilter(new ColorMatrixColorFilter(mColorMatrix));
registerActivityLifecycleCallbacks(new ActivityLifecycleCallbacks() {
@Override
public void onActivityCreated(@NonNull Activity activity, @Nullable Bundle savedInstanceState) {
// 当Activity创建,我们拿到DecorView,使用Paint进行重绘
View decorView = activity.getWindow().getDecorView();
decorView.setLayerType(View.LAYER_TYPE_HARDWARE, mPaint);
}
....
});
}
}
方案一:给Activity的顶层View设置置灰,实现全局置灰效果
可以在BaseActivity的onCreate方法中,使用ColorMatrix设置灰度
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//方案一
Paint paint = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);//灰度效果
paint.setColorFilter(new ColorMatrixColorFilter(cm));
getWindow().getDecorView().setLayerType(View.LAYER_TYPE_HARDWARE,paint);
}
方案二:该方法使用自定义layout,在dispatchdraw方法的时候,添加一层黑白色的bitmap,让界面开起来成为黑白模式。
先定义一个GrayFrameLayout布局
public class GrayFrameLayout extends FrameLayout {
private Paint mPaint = new Paint();
public GrayFrameLayout(@NonNull Context context) {
super(context);
}
public GrayFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
mPaint.setColorFilter(new ColorMatrixColorFilter(cm));
}
@Override
protected void onDraw(Canvas canvas) {
canvas.saveLayer(null, mPaint, Canvas.ALL_SAVE_FLAG);
super.onDraw(canvas);
}
@Override
protected void dispatchDraw(Canvas canvas) {
canvas.saveLayer(null, mPaint, Canvas.ALL_SAVE_FLAG);
super.dispatchDraw(canvas);
}
}
在BaseActivity的onCreateView方法中做如下处理:
@Override
public View onCreateView(View parent, String name, Context context, AttributeSet attrs {
//方案二
if("FrameLayout".equals(name)){
int attributeCount = attrs.getAttributeCount();
for (int i = 0; i < attributeCount; i++) {
String attributeName = attrs.getAttributeName(i);
String attributeValue = attrs.getAttributeValue(i);
if(attributeName.equals("id")){
int id = Integer.parseInt(attributeValue.substring(1));
String resourceName = getResources().getResourceName(id);
if("android:id/content".equals(resourceName)){
GrayFrameLayout frameLayout = new GrayFrameLayout(this,attrs);
return frameLayout;
}
}
}
}
return super.onCreateView(parent, name, context, attrs);
}
方案三:有些特殊控件需要置灰,比如webview、H5页面、视频等
//硬件加速置灰方法
public void setLayerGrayType(View view) {
if (mGrayMatrix == null || mGrayPaint == null) {
init();
}
view.setLayerType(View.LAYER_TYPE_HARDWARE, mGrayPaint);
}
特殊控件需要置灰的话直接调用setLayerGrayType()方法将view传进去,比如demo中让某个Activity置灰,那就在Activity里面调用:
GrayManager.getInstance().setLayerGrayType(getWindow().getDecorView());