我正在为Android制作钢琴应用程序。作为样本(测试),我的活动中有4个按钮。父亲是Relative Layout
,我也有几个文本视图,告诉手指触摸的屏幕坐标。还有一个textView(“输入按钮”)可以检测手指是否在按钮上方。这就是它的样子:
我使用下面给出的代码实现了这一点。
爪哇
public class MainActivity extends Activity {
Button b1, b2, b3, b4;
int b1x1, b1x2, b1y1, b1y2;
private TextView xcordview;
private TextView ycordview;
private TextView buttonIndicator;
private RelativeLayout touchview;
private static int defaultStates[];
private Button mLastButton;
private final static int[] STATE_PRESSED = {
android.R.attr.state_pressed,
android.R.attr.state_focused
| android.R.attr.state_enabled };
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
xcordview = (TextView) findViewById(R.id.textView4);
ycordview = (TextView) findViewById(R.id.textView3);
buttonIndicator = (TextView) findViewById(R.id.button_indicator);
touchview = (RelativeLayout) findViewById(R.id.relativelayout);
b1 = (Button) findViewById(R.id.button1);
b2 = (Button) findViewById(R.id.button2);
b3 = (Button) findViewById(R.id.button3);
b4 = (Button) findViewById(R.id.button4);
defaultStates = b1.getBackground().getState();
}
@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
touchview.setOnTouchListener(new View.OnTouchListener() {
private boolean isInside = false;
@Override
public boolean onTouch(View v, MotionEvent event) {
int x = (int) event.getX();
int y = (int) event.getY();
xcordview.setText(String.valueOf(x));
ycordview.setText(String.valueOf(y));
for (int i = 0; i < touchview.getChildCount(); i++) {
View current = touchview.getChildAt(i);
if (current instanceof Button) {
Button b = (Button) current;
if (!isPointWithin(x, y, b.getLeft(), b.getRight(), b.getTop(),
b.getBottom())) {
b.getBackground().setState(defaultStates);
}
if (isPointWithin(x, y, b.getLeft(), b.getRight(), b.getTop(),
b.getBottom())) {
b.getBackground().setState(STATE_PRESSED);
if (b != mLastButton) {
mLastButton = b;
buttonIndicator.setText(mLastButton.getText());
}
}
}
}
return true;
}
});
}
@Override
public void onWindowFocusChanged(boolean hasFocus) {
// TODO Auto-generated method stub
super.onWindowFocusChanged(hasFocus);
}
static boolean isPointWithin(int x, int y, int x1, int x2, int y1, int y2) {
return (x <= x2 && x >= x1 && y <= y2 && y >= y1);
}
}
XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/relativelayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff" >
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_marginBottom="10dp"
android:layout_marginLeft="10dp"
android:text="Y Cord : "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView"
android:layout_alignParentLeft="true"
android:layout_marginBottom="10dp"
android:layout_marginLeft="10dp"
android:text="X Cord : "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView2"
android:layout_toRightOf="@+id/textView"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#000000" />
<TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView"
android:layout_marginBottom="10dp"
android:layout_toRightOf="@+id/textView"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#000000" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:text="B1"
android:textColor="#000000" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/button1"
android:text="B2"
android:textColor="#000000" />
<Button
android:id="@+id/button3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/button2"
android:text="B3"
android:textColor="#000000" />
<Button
android:id="@+id/button4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/button3"
android:text="B4"
android:textColor="#000000" />
<TextView
android:id="@+id/button_indicator"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignTop="@+id/textView4"
android:layout_marginRight="33dp"
android:text="No one"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/button_indicator"
android:layout_alignBottom="@+id/button_indicator"
android:layout_marginRight="29dp"
android:layout_toLeftOf="@+id/button_indicator"
android:text="Entered: "
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>
所以上面给出的代码工作得很好,因为当我从任何按钮上的白色空间(相对布局)上滑动手指时它会识别出来。但是当我从按钮滑动到另一个按钮时,它不起作用。它没有得到任何坐标,也没有感觉到我的手指在哪个按钮上。下图说明了从按钮滑动到另一个按钮时最佳情况。
那么在从一个按钮滑动到另一个按钮的同时如何获取坐标?
答案 0 :(得分:4)
MainActivity.java
package com.example.touch;
import android.app.Activity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TextView;
public class MainActivity extends Activity {
MyButton b1, b2, b3, b4;
int b1x1, b1x2, b1y1, b1y2;
private TextView xcordview;
private TextView ycordview;
private TextView buttonIndicator;
private RelativeLayout touchview;
private static int defaultStates[];
private Button mLastButton;
private final static int[] STATE_PRESSED = {
android.R.attr.state_pressed,
android.R.attr.state_focused
| android.R.attr.state_enabled };
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
xcordview = (TextView) findViewById(R.id.textView4);
ycordview = (TextView) findViewById(R.id.textView3);
buttonIndicator = (TextView) findViewById(R.id.button_indicator);
touchview = (RelativeLayout) findViewById(R.id.relativelayout);
b1 = (MyButton) findViewById(R.id.button1);
b2 = (MyButton) findViewById(R.id.button2);
b3 = (MyButton) findViewById(R.id.button3);
b4 = (MyButton) findViewById(R.id.button4);
defaultStates = b1.getBackground().getState();
}
@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
touchview.setOnTouchListener(new View.OnTouchListener() {
private boolean isInside = false;
@Override
public boolean onTouch(View v, MotionEvent event) {
int x = (int) event.getX();
int y = (int) event.getY();
xcordview.setText(String.valueOf(x));
ycordview.setText(String.valueOf(y));
for (int i = 0; i < touchview.getChildCount(); i++) {
View current = touchview.getChildAt(i);
if (current instanceof Button) {
Button b = (Button) current;
if (!isPointWithin(x, y, b.getLeft(), b.getRight(), b.getTop(),
b.getBottom())) {
b.getBackground().setState(defaultStates);
b.getBackground().setAlpha(255);
}
if (isPointWithin(x, y, b.getLeft(), b.getRight(), b.getTop(),
b.getBottom())) {
b.getBackground().setState(STATE_PRESSED);
b.getBackground().setAlpha(150);
b.performClick();
if (b != mLastButton) {
mLastButton = b;
buttonIndicator.setText(mLastButton.getText());
}
}
}
}
return true;
}
});
}
@Override
public void onWindowFocusChanged(boolean hasFocus) {
// TODO Auto-generated method stub
super.onWindowFocusChanged(hasFocus);
}
static boolean isPointWithin(int x, int y, int x1, int x2, int y1, int y2) {
return (x <= x2 && x >= x1 && y <= y2 && y >= y1);
}
}
MyButton.java
package com.example.touch;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.Button;
public class MyButton extends Button {
public MyButton(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// TODO Auto-generated constructor stub
}
public MyButton(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
public MyButton(Context context) {
super(context);
// // TODO Auto-generated constructor stub
}
@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
// return super.onTouchEvent(event);
return false;
}
}
布局:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/relativelayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff" >
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_marginBottom="10dp"
android:layout_marginLeft="10dp"
android:text="Y Cord : "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView"
android:layout_alignParentLeft="true"
android:layout_marginBottom="10dp"
android:layout_marginLeft="10dp"
android:text="X Cord : "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView2"
android:layout_toRightOf="@+id/textView"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#000000" />
<TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView"
android:layout_marginBottom="10dp"
android:layout_toRightOf="@+id/textView"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#000000" />
<com.example.touch.MyButton
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:text="B1"
android:textColor="#000000" />
<com.example.touch.MyButton
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/button1"
android:text="B2"
android:textColor="#000000" />
<com.example.touch.MyButton
android:id="@+id/button3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/button2"
android:text="B3"
android:textColor="#000000" />
<com.example.touch.MyButton
android:id="@+id/button4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/button3"
android:text="B4"
android:textColor="#000000" />
<TextView
android:id="@+id/button_indicator"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignTop="@+id/textView4"
android:layout_marginRight="33dp"
android:text="No one"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/button_indicator"
android:layout_alignBottom="@+id/button_indicator"
android:layout_marginRight="29dp"
android:layout_toLeftOf="@+id/button_indicator"
android:text="Entered: "
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>