按下按鈕以切換活動時強制關閉

Question

我是計算機科學專業的學生，​​並且是Android編程的新手。 我正在嘗試創建一個應用程序，該應用程序允許編輯圖像，然后將其放置在文件夾中以作為一種幻燈片進行查看，或者將完成的圖像共享到社交媒體網站。

我目前有一個遇到麻煩的代碼，涉及到通過按下按鈕在活動之間進行切換。 每當我在手機上運行該應用程序時，在我按按鈕進入“發送電子郵件”活動（導致其強制關閉）之前，它都可以正常工作。 當我自己運行它時，發送電子郵件的第二個活動效果很好。 但問題是將其鏈接到我的主要活動。

我嘗試使用我在Internet上找到的代碼來切換到新活動，但是它似乎不起作用。 我知道這應該是一個簡單的解決方法，但是我似乎無法確切找到我要去哪里。

以下是我使用和編輯的源代碼：

---

AndroidManifest.xml （包括用於Aviary SDK的代碼）

第二個活動是代碼最底部的send_mail活動。

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

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="19" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
    android:allowBackup="true"
    android:icon="@drawable/icon_launcher"
    android:label="@string/app_name"
   android:theme="@android:style/Theme.Black.NoTitleBar.Fullscreen">
     <meta-data
    android:name="com.aviary.android.feather.v1.API_KEY"
    android:value="6cedc33767b3b37c" />

     <activity
android:name="com.aviary.android.feather.FeatherActivity"
android:configChanges="orientation|keyboardHidden|screenSize"
android:screenOrientation="unspecified"
android:hardwareAccelerated="true"
android:largeHeap="true"
android:process=":aviarysdk"
android:theme="@style/AviaryTheme" />
     <activity
    android:name="com.aviary.android.feather.AlertActivity"
    android:launchMode="standard"
    android:noHistory="true"
    android:theme="@style/AviaryTheme.Dialog">
    <intent-filter>
        <action android:name="aviary.intent.action.ALERT"/>
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

<!-- CDS Content Service -->
<service
    android:process=":aviarycds"
    android:name="com.aviary.android.feather.cds.AviaryCdsService"
    android:exported="false">
    <intent-filter>
        <action android:name="aviary.intent.action.CDS_DOWNLOAD_START"/>
        <action android:name="aviary.intent.action.CDS_RESTORE_USER_ITEMS"/>
    </intent-filter>
</service> 

<!-- 
    Cds Content Provider, 
    NOTE that the "authorities" value MUST be formatted in this way:
    android:authorities="{your.packagename}.AviaryCdsProvider"
 -->
<provider
    android:name="com.aviary.android.feather.cds.AviaryCdsProvider"
    android:authorities="com.fiverr.instafiverr.AviaryCdsProvider"
    android:process=":aviarycds"
    android:exported="false"
    android:syncable="true" />  

<!-- CDS Download Receiver -->
<receiver 
    android:name="com.aviary.android.feather.cds.AviaryCdsReceiver"
    android:process=":aviarycds" >
    <intent-filter>
        <action android:name="android.intent.action.DOWNLOAD_COMPLETE" />
    </intent-filter>
</receiver>
    <activity
        android:name="com.fiverr.instafiverr.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.fiverr.instafiverr.DisplayImage"
        android:label="@string/app_name" />

      <activity
        android:name="com.fiverr.instafiverr.send_mail"
        android:label="@string/app_name" />
</application>

</manifest>

---

MainActivity.java

這是我的第一個活動。

package com.fiverr.instafiverr;

import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

import com.aviary.android.feather.FeatherActivity;
import com.aviary.android.feather.library.Constants;

public class MainActivity extends Activity {
private static final int CAMERA_REQUEST = 10;
private static final int Gallery_Request = 20;
Button Camera;
Button Gallery;
Button Email;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Camera=(Button) findViewById(R.id.button1);
    Gallery=(Button) findViewById(R.id.button2);
    Email= (Button) findViewById(R.id.button4); 


    Email.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            Intent emailIntent = new Intent(MainActivity.this, send_mail.class);
                startActivity(emailIntent);
            }
        }); 

    Camera.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
             Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); 
                startActivityForResult(cameraIntent, CAMERA_REQUEST); 
        }
    });

    Gallery.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            Intent i = new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(i, Gallery_Request);
        }
    }); 

}

@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;
}

public void LaunchInstaFiverr(Uri uri){


    Intent newIntent = new Intent( this, FeatherActivity.class );
    newIntent.setData( uri );
    newIntent.putExtra( Constants.EXTRA_IN_API_KEY_SECRET, "6cedc33767b3b37c" );
    startActivityForResult( newIntent, 1 );  
}
@Override
public void onActivityResult( int requestCode, int resultCode, Intent data ) {
    if( resultCode == RESULT_OK ) {
        switch( requestCode ) {
            case 1:
                // output image path
                Uri mImageUri = data.getData();

                Appdata.uri=mImageUri;

                Intent intent= new Intent(this, DisplayImage.class);

                startActivity(intent);

                Bundle extra = data.getExtras();
                    if( null != extra ) {
                        // image has been changed by the user?
                        boolean changed = extra.getBoolean( Constants.EXTRA_OUT_BITMAP_CHANGED );
                    }
                break;

            case CAMERA_REQUEST:{
                   // Bitmap photo = (Bitmap) data.getExtras().get("data"); 
                    Uri imageUri = data.getData();

                    LaunchInstaFiverr(imageUri);
               break;
        }
            case Gallery_Request:{
                   // Bitmap photo = (Bitmap) data.getExtras().get("data"); 
                    Uri imageUri = data.getData();

                    LaunchInstaFiverr(imageUri);

                    break;

        }
}}}}

---

send_mail.java

這是應該在單擊“電子郵件”按鈕（button4）時打開的第二個活動。

package com.fiverr.instafiverr;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.text.Html;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;


public class send_mail extends Activity implements OnClickListener{
EditText To, Subject, Message;
Button Send;
@Override
protected void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.send_email);
    Subject = (EditText)findViewById(R.id.editText2);
    Message = (EditText)findViewById(R.id.editText3);
    Send = (Button)findViewById(R.id.button1);
    Send.setOnClickListener(this);
}
@Override
public void onClick(View args0) {
    Intent i = new Intent(android.content.Intent.ACTION_SEND);
    i.putExtra(android.content.Intent.EXTRA_EMAIL, new String[] {"devangelic_art@yahoo.com"});
    i.putExtra(android.content.Intent.EXTRA_SUBJECT, Subject.getText().toString());
    i.putExtra(android.content.Intent.EXTRA_TEXT, Html.fromHtml(Message.getText().toString()));
    i.setType("text/html");
    startActivity(Intent.createChooser(i, "Choose an email client:"));
    finish();
}
}

---

activity_main.xml中

這是第一個活動的布局。

<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:background="@drawable/background"
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" >

<ImageView
    android:id="@+id/imageView1"
    android:layout_width="wrap_content"
    android:layout_height="150dp"
    android:layout_gravity="center"
    android:layout_marginBottom="10dp"
    android:layout_marginTop="15dp"
    android:scaleType="fitCenter"
    android:src="@drawable/title"
    android:contentDescription="@string/title" />

<Button
    android:id="@+id/button2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_alignParentTop="true"
    android:layout_marginTop="196dp"
    android:background="@drawable/button_create" />

<Button
    android:id="@+id/button4"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/button3"
    android:layout_marginTop="15dp"
    android:layout_marginLeft="10dp"
    android:layout_centerHorizontal="true"
    android:background="@drawable/button_help" />

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/button4"
    android:layout_marginTop="15dp"
    android:layout_marginRight="10dp"
    android:layout_centerHorizontal="true"
    android:background="@drawable/buttonxml"
    android:text="@string/camera"
    android:textColor="#ffffff"
    android:textSize="30sp" />

<Button
    android:id="@+id/button3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/button4"
    android:layout_below="@+id/button2"
    android:layout_marginLeft="18dp"
    android:layout_marginTop="15dp"
    android:background="@drawable/button_albums" />

</RelativeLayout>

---

send_email.xml 這是第二個活動的布局。

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="fill_vertical|fill_horizontal"
android:layout_margin="20dp"
android:background="@drawable/background"
android:orientation="vertical"
android:padding="10dp"
android:scrollbars="vertical" >

<TextView
    android:id="@+id/textView4"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:layout_marginBottom="15dp"
    android:text="@string/mail"
    android:textAlignment="center"
    android:textAppearance="?android:attr/textAppearanceLarge" />

<TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/subject"
    android:textAppearance="?android:attr/textAppearanceMedium" />

<EditText
    android:id="@+id/editText2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginBottom="5dp"
    android:ems="10"
    android:inputType="textEmailSubject" />

<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/message"
    android:textAppearance="?android:attr/textAppearanceMedium" />

<EditText
    android:id="@+id/editText3"
    android:layout_width="match_parent"
    android:layout_height="150dp"
    android:ems="10"
    android:inputType="textMultiLine"
    android:scrollbars="vertical" />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="0dp"
    android:layout_weight="1"
    android:gravity="center|bottom" >

    <Button
        android:id="@+id/button1"
        style="?android:attr/buttonStyleSmall"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/send" />

</LinearLayout>

</LinearLayout>

---

原木貓

07-10 19:32:53.900: E/AndroidRuntime(5969): FATAL EXCEPTION: main
07-10 19:32:53.900: E/AndroidRuntime(5969): android.app.SuperNotCalledException: Activity {com.fiverr.instafiverr/com.fiverr.instafiverr.send_mail} did not call through to super.onCreate()
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2169)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.app.ActivityThread.access$600(ActivityThread.java:150)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1301)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.os.Handler.dispatchMessage(Handler.java:99)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.os.Looper.loop(Looper.java:153)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at android.app.ActivityThread.main(ActivityThread.java:5105)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at java.lang.reflect.Method.invokeNative(Native Method)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at java.lang.reflect.Method.invoke(Method.java:511)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
07-10 19:32:53.900: E/AndroidRuntime(5969):     at dalvik.system.NativeStart.main(Native Method)

---

預期結果 ：按下主頁上的按鈕將打開用於發送電子郵件的活動。

任何幫助將不勝感激。 希望社會各界給予積極響應。 感謝您抽出時間閱讀我的帖子。

Answer 1

您必須調用超級活動的生命周期方法。 因此，只需嘗試添加它：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);//this line must exist
    setContentView(R.layout.send_email);
    Subject = (EditText)findViewById(R.id.editText2);
    Message = (EditText)findViewById(R.id.editText3);
    Send = (Button)findViewById(R.id.button1);
    Send.setOnClickListener(this);
}

Answer 2

您必須在send_mail.java文件的onCreate（）方法中調用super.onCreate（）（必須是onCreate（）的該塊的第一行）。 看到這個問題super.onCreate（savedInstanceState）;