android —— PopupWindow

一、常用方法：

1、设置显示的位置

// 一个参数
popupWindow.showAsDropDown(v);
//参数1: popupWindow关联的view
// 参数2和3：相对于关联控件的偏移量
 popupWindow.showAsDropDown(View anchor, int xoff, int yoff)

2、是否会获取焦点

popupWindow.setFocusable(true);

3、设置背景

 //  popupWindow添加背景色
popupWindow.setBackgroundDrawable(ResourcesCompat.getDrawable(getResources(),R.drawable.img1,getTheme()));

4、关闭

popupWindow.dismiss();

5、设置加载动画

 popupWindow.setAnimationStyle(R.anim.alpha); //设置动画

6、设置触摸使能和popupwindow外部的触摸使能

 popupWindow.setTouchable(true);
popupWindow.setOutsideTouchable(true);

二、实例：

1、新建一个popupwindow要显示使用的xml文件popupview.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <androidx.appcompat.widget.AppCompatButton
        android:id="@+id/mBtn1"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:text="测试1"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        />
    <androidx.appcompat.widget.AppCompatButton
        android:id="@+id/mBtn2"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:text="测试2"
        android:layout_marginTop="10dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@id/mBtn1"
        />
</androidx.constraintlayout.widget.ConstraintLayout>

2、在activity中使用：

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_tween_anim);
        Button button=findViewById(R.id.btn);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                popupClick(v);
            }
        });
    }

    private void popupClick(View v) {
//        添加对应的view
        View popupView = getLayoutInflater().inflate(R.layout.popup_view, null);
        Button mBtn1=popupView.findViewById(R.id.mBtn1);
        Button mBtn2=popupView.findViewById(R.id.mBtn2);
//        ViewGroup.LayoutParams.WRAP_CONTENT: popupWindow包裹popupView
//        第四个参数为true，点击空白处popupWindow关闭
        PopupWindow popupWindow = new PopupWindow(popupView, ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT,true);
        //        popupWindow添加背景色
        popupWindow.setBackgroundDrawable(ResourcesCompat.getDrawable(getResources(),R.drawable.img1,getTheme()));
        popupWindow.setAnimationStyle(R.anim.alpha); //设置动画
//        popupWindow.showAsDropDown(v);
//        参数2和参数3是设置偏移量
        popupWindow.showAsDropDown(v,popupView.getWidth(),-popupView.getHeight());

        mBtn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                popupWindow.dismiss();
            }
        });
        mBtn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                popupWindow.dismiss();
            }
        });
    }