我试图让我的应用程序导航到按钮单击的另一个活动,但每当我这样做时,应用程序只是崩溃。我不明白为什么会这样。
我在add.java
页面中的代码,该代码将处理按钮点击并导航到其他类WifiConnections
add.java中的代码
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add);
addListenerOnButton();
}
public void addListenerOnButton() {
final Context context = this;
Button button = (Button) findViewById(R.id.addb);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
Intent intent = new Intent(context, WifiConnections.class);
startActivity(intent);
}
});
}
但是,当我将Wificonnections.xml设置为清单文件中的起始布局时,wifi连接部分工作正常,但在尝试导航时崩溃。
Android清单
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.abhi.myapplication2">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme">
<activity
android:name=".login"
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:label="@string/app_name"
android:name=".WifiConnections" >
</activity>
<activity
android:label="@string/app_name"
android:name=".add" >
</activity>
<activity
android:label="@string/app_name"
android:name=".signup" >
</activity>
</application>
</manifest>
WifiConnections Oncreate方法
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.wifi_connections);
mainText = (TextView) findViewById(R.id.mainText);
// Initiate wifi service manager
mainWifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
// Check for wifi is disabled
if (mainWifi.isWifiEnabled() == false)
{
// If wifi disabled then enable it
Toast.makeText(getApplicationContext(), "wifi is disabled..making it enabled",
Toast.LENGTH_LONG).show();
mainWifi.setWifiEnabled(true);
}
// wifi scaned value broadcast receiver
receiverWifi = new WifiReceiver();
// Register broadcast receiver
// Broacast receiver will automatically call when number of wifi connections changed
registerReceiver(receiverWifi, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
mainWifi.startScan();
mainText.setText("Starting Scan...");
}
add.xml代码
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:fillViewport="true">
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/layout_add">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/addb"
style="@android:style/Widget.Material.Button.Borderless"
android:background="@drawable/add"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="110dp"
android:layout_marginLeft="100dp"
android:layout_marginRight="60dp"
android:layout_marginBottom="170dp"
android:onClick="addclick"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="No device added"
android:id="@+id/textView"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="130dp"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Click to add device"
android:id="@+id/textView2"
android:layout_alignTop="@+id/textView"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:textSize="20sp" />
</RelativeLayout>
</ScrollView>
完整的项目 http://www37.zippyshare.com/v/10112230/file.html
LogCat在这里:
12-25 09:28:10.460 1952-1952/android.techbreeze.in W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0xb0ec4648)
12-25 09:28:10.470 1952-1952/android.techbreeze.in E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.IllegalStateException: Could not find a method addclick(View) in the activity class com.example.abhi.myapplication2.login for onClick handler on view class android.widget.Button with id 'addb'
at android.view.View$1.onClick(View.java:3620)
at android.view.View.performClick(View.java:4240)
at android.view.View$PerformClick.run(View.java:17721)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NoSuchMethodException: addclick [class android.view.View]
at java.lang.Class.getConstructorOrMethod(Class.java:423)
at java.lang.Class.getMethod(Class.java:787)
at android.view.View$1.onClick(View.java:3613)
at android.view.View.performClick(View.java:4240)
at android.view.View$PerformClick.run(View.java:17721)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
答案 0 :(得分:1)
删除这些行,
style="@android:style/Widget.Material.Button.Borderless"
android:onClick="addclick"
在add.xml
答案 1 :(得分:1)
从“adb”按钮
删除android:onClick =“添加点击”答案 2 :(得分:0)
我看到两种解决这个问题的方法。 首先:在onCreate方法中初始化Context变量,如下所示:
public class SomeActivity extends Activity{
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add);
addListenerOnButton();
contex = this;
}
...
}
第二:做同样的事情,仍然不使用this
,而是使用以下内容:
contex = getApplicationContext();
因为Intent非常喜欢使用应用程序上下文。
答案 3 :(得分:0)
试试这个
Intent intent = new Intent(Add.this, WifiConnections.class);
并删除
final Context context = this;
希望它有帮助...:)