我正在创建一个应用程序，它有一个按钮，点击后必须打开谷歌地图。但onclick它是空白的！我已经使用了意图，还有其他方法可以将谷歌地图加载到我的应用程序中吗？我的代码有什么问题？我错过了什么？
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<Button
android:id="@+id/button1"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="14dp"
android:text="MAPS" />
</RelativeLayout>
MainaActivity.java
package com.stayconnected;
import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
Button button1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addListenerOnButton();
}
public void addListenerOnButton() {
final Context context = this;
button1 = (Button) findViewById(R.id.button1);
button1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
Intent intent = new Intent(context, MainActivity2.class);
startActivity(intent);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
MainActivity.java
package com.stayconnected;
import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.Menu;
public class MainActivity2 extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
String url = "http://maps.google.com/maps?saddr=" + "9982878"+","+"76285774"+"&daddr="+"9992084"+","+"76286455";
Intent intent1 = new Intent(android.content.Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent1);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
AndroiManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.stayconnected"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.stayconnected.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.stayconnected.MainActivity2"
android:label="@string/app_name" >
</activity>
</application>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
</manifest>
我必须下载谷歌地图密钥或其他东西吗？因为我在互联网上读到要在我的应用程序活动中加载谷歌地图，所以我必须下载密钥，然后地图才能工作！这就是我遇到这个问题的原因吗？