Question

我正在测试我的第一个真正的应用程序，这非常简单。（我已经测试了一个简单的hello world one）不幸的是我的应用程序没有显示在AVD中。我有两个类和我的AndroidManifest.xml文件我的第一个名为CrazyEightActivity.java的班级有这个代码，

package com.example.crazyeights;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class CrazyEightsActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        CrazyEightsView CrazyEightsView = new CrazyEightsView(this);
        setContentView(R.layout.activity_main);
    }
}

我的第二个名为CrazyEightsView.java的班级有：

package com.example.crazyeights;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.view.View;

public class CrazyEightsView extends View
{
    private Paint redPaint;
    private int circleX;
    private int circleY;
    private float radius;

public CrazyEightsView(Context context) {
        super(context);
        redPaint = new Paint();
        redPaint.setAntiAlias(true);
        redPaint.setColor(Color.RED);
        circleX = 100;
        circleY = 100;
        radius = 30;
    }
    @Override
    protected void onDraw(Canvas canvas)
    {
        canvas.drawCircle(circleX, circleY, radius, redPaint);
    }

}

最后我的.xml有：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.crazyeights"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="18" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.crazyeights.CrazyEightsActivity" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    </application>

</manifest>

我很抱歉这么多代码，这可能会让它变得无法抗拒，所以感谢您的帮助！

Answer 1

CrazyEightsView CrazyEightsView = new CrazyEightsView(this);


setContentView(CrazyEightsView);

你的xml布局中似乎没有任何东西！将您的活动视图设置为自定义视图

Answer 2

您尚未将自定义视图附加到Activity

简单的应用程序不会在AVD中显示

2 个答案: