我的RelativeLayout中有两个ImageView.我可以通过触摸并将其拖动到屏幕上的任何位置来移动图像.
图像在可绘制文件夹中
但是现在我想要以下内容：
>用户在屏幕上触摸过的任何地方都应显示相同的内容
图片.
>拖动时继续显示图像(不删除上一个)
图片.
Sample Screenshot of what I want to do
activity_main.xml
@H_404_17@<?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:id="@+id/relativeLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<ImageView
android:id="@+id/backgroundIv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_alignParentBottom="true"
android:layout_centerInParent="true"
android:scaleType="fitXY"
android:src="@drawable/windows_xp_desktop" />
<ImageView
android:id="@+id/foregroundIv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:scaleType="fitXY"
android:src="@drawable/win_xp_error" />
</RelativeLayout>
主要活动
@H_404_17@package com.example.myapplication;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.ImageView;
import android.widget.RelativeLayout;
public class MainActivity extends AppCompatActivity {
ImageView backgroundIv,foregroundIv;
RelativeLayout relativeLayout;
private ViewGroup rootLayout;
private int xDelta;
private int yDelta;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Hiding Title bar of this activity screen */
getWindow().requestFeature(Window.FEATURE_NO_TITLE);
//Making this activity,full screen */
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
backgroundIv = findViewById(R.id.backgroundIv);
foregroundIv = findViewById(R.id.foregroundIv);
relativeLayout = findViewById(R.id.relativeLayout);
RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(350,200);
foregroundIv.setLayoutParams(layoutParams);
foregroundIv.setOnTouchListener(new ChoiceTouchListener());
}
private class ChoiceTouchListener implements View.OnTouchListener {
@Override
public boolean onTouch(View v,MotionEvent event) {
final int X = (int) event.getRawX();
final int Y = (int) event.getRawY();
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) v.getLayoutParams();
xDelta = X - lParams.leftMargin;
yDelta = Y - lParams.topMargin;
break;
case MotionEvent.ACTION_UP:
break;
case MotionEvent.ACTION_POINTER_DOWN:
break;
case MotionEvent.ACTION_POINTER_UP:
break;
case MotionEvent.ACTION_MOVE:
RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) v.getLayoutParams();
layoutParams.leftMargin = X - xDelta;
layoutParams.topMargin = Y - yDelta;
layoutParams.rightMargin = -250;
layoutParams.bottomMargin = -250;
v.setLayoutParams(layoutParams);
break;
}
relativeLayout.invalidate();
return true;
}
}
}
最佳答案
像这样做
@H_404_17@
原文链接：https://www.f2er.com/android/531383.htmlpublic class MainActivity extends AppCompatActivity {
ImageView backgroundIv,foregroundIv;
RelativeLayout relativeLayout;
private ViewGroup rootLayout;
private int xDelta;
private int yDelta;
private ChoiceTouchListener listener;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
foregroundIv = findViewById(R.id.foregroundIv);
relativeLayout = findViewById(R.id.relativeLayout);
RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(350,200);
foregroundIv.setLayoutParams(layoutParams);
listener = new ChoiceTouchListener();
foregroundIv.setOnTouchListener(listener);
}
private void addNewImage(int X,int Y) {
ImageView img = new ImageView(this);
img.setImageResource(R.drawable.mcblauhp);
img.setScaleType(ImageView.ScaleType.FIT_XY);
img.setOnTouchListener(listener);
relativeLayout.addView(img);
RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) img.getLayoutParams();
lParams.leftMargin = X;
lParams.topMargin = Y;
img.setLayoutParams(lParams);
}
private class ChoiceTouchListener implements View.OnTouchListener {
@Override
public boolean onTouch(View v,MotionEvent event) {
final int X = (int) event.getRawX();
final int Y = (int) event.getRawY();
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) v.getLayoutParams();
xDelta = X - lParams.leftMargin;
yDelta = Y - lParams.topMargin;
//addNewImage(lParams.leftMargin,lParams.topMargin);
//v.bringToFront(); // this is to ensure that the moved image is always on top
break;
case MotionEvent.ACTION_UP:
break;
case MotionEvent.ACTION_POINTER_DOWN:
break;
case MotionEvent.ACTION_POINTER_UP:
break;
case MotionEvent.ACTION_MOVE:
RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) v.getLayoutParams();
addNewImage(layoutParams.leftMargin,layoutParams.topMargin);
v.bringToFront();
layoutParams.leftMargin = X - xDelta;
layoutParams.topMargin = Y - yDelta;
layoutParams.rightMargin = -250;
layoutParams.bottomMargin = -250;
v.setLayoutParams(layoutParams);
break;
}
relativeLayout.invalidate();
return true;
}
}
}
