I could solve it erasing an application that I had previously uploaded using the same Bundle Identifier (xcode get's confused doing the chmod). 

Try checking the log from xCode Organizer (Your device's Name -> Console) you should get information from that log.

because i already have the same app using the same bundle identifier installed on the phone. 

- what you need to do is to delete all those apps on your iphone which is using the same bundle identifier name

原理图：

1)main.xml

就是把上面的左边的那个布局画出来

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <TextView 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="用户名"
        />

    <EditText 
        android:id="@+id/et_username"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        />
    
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="get"
        android:text="获取"
        />
</LinearLayout>

2)main2.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    

    <ListView 
        android:id="@+id/listview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />
</LinearLayout>

3)MainActivity

package com.njupt.openactivityforresult;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;

public class MainActivity extends Activity {

	private EditText et_username;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		
		et_username = (EditText) findViewById(R.id.et_username);
	}
	
	public void get(View v){
		
		Intent intent = new Intent(this,Main2Activity.class);
		
		startActivityForResult(intent,100);
	}

	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		super.onActivityResult(requestCode, resultCode, data);
	    
		if(requestCode == 100){
			if(data != null){
				String username = data.getStringExtra("username");
				et_username.setText(username);
			}
		}
	}
	
	@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;
	}

}

package com.njupt.openactivityforresult;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class Main2Activity extends Activity {

	private ListView listview;
	private MyBaseAdapter adapter;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main2);
		
		listview = (ListView) findViewById(R.id.listview);
		
		adapter = new MyBaseAdapter();
		listview.setAdapter(adapter);
		listview.setOnItemClickListener(new MyOnItemClickListener());
	}
	
	private class MyOnItemClickListener implements OnItemClickListener{
		
		@Override
		public void onItemClick(AdapterView<?> parent, View view, int position,
				long id) {
			
			//在listview中获取某一item的方法1:
//			Intent intent = new Intent();
//			String username = (String) adapter.getItem(position);
//			intent.putExtra("username", username);
//			setResult(200,intent);
//			finish();
			
			//在listview中获取某一item的方法2:
			String username = (String) parent.getItemAtPosition(position);
			Intent intent = new Intent();
			intent.putExtra("username",username);
			setResult(200, intent);
			finish();
		}
	}
	private class MyBaseAdapter extends BaseAdapter{
		String[] names = new String[]{"章泽天","章泽天1","章泽天2","章泽天3","章泽天4"};
		
		public int getCount() {
			return names.length;
		}
		
		@Override
		public Object getItem(int position) {
			return names[position];
		}
		
		@Override
		public long getItemId(int position) {
			return position;
		}
		
		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			
			TextView tv = new TextView(getApplicationContext());
			tv.setText(names[position]);
			tv.setTextSize(25);
			tv.setTextColor(Color.GREEN);
			return tv;
		}
	}
}

5)AndroidManifest.xml

还是那一句话，最后别忘了在清单文件中吧Main2Activity注册上

<activity android:name="com.njupt.openactivityforresult.Main2Activity" android:label="选择联系人"/>

配置：

在AndroidManifest.xml中找到<activity/>并在里面配上android:launchMode="启动模式" 

如：

<activity android:name="com.njupt.luanchmode.Main2Activity" android:label="B界面"android:launchMode="singleInstance" />

常见类型(个人理解)：

 1)standard：不改变操作序列 .什么叫操作序列，例如你先进入A，在进入B，接着又进入A，最后又进入B。

那么你的操作序列就是A ----- >> B ------ >> A -------->>B。所以退出时的顺序就是反过来以后的结果

B------->>A------->>B------->>A

 2)singleTop:合并相邻的重复项

 3)singleTask:合并重复项

 4)singleInstance:始终只保留最新的那一个 

原理图：

  1)standard:

2)singleTop

3)singleTask

4)singleInsatnce

实现如下：

1、main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <TextView 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="A界面"
        />
    
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="打开A界面"
        android:onClick="open1"
        />
    
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="打开B界面"
        android:onClick="open2"
        />
</LinearLayout>

package com.njupt.luanchmode;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
	}

	public void open1(View v){
		Intent intent = new Intent(this,MainActivity.class);
		
		startActivity(intent);
	}
	
	public void open2(View v){
		Intent intent = new Intent(this,Main2Activity.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;
	}

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <TextView 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="B界面"
        />
    
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="打开A界面"
        android:onClick="open1"
        />
    
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="打开B界面"
        android:onClick="open2"
        />
</LinearLayout>

package com.njupt.luanchmode;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;

public class Main2Activity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
	    
		setContentView(R.layout.main2);
	}
	
	public void open1(View v){
		Intent intent = new Intent(this,MainActivity.class);
		
		startActivity(intent);
	}
	
	public void open2(View v){
		Intent intent = new Intent(this,Main2Activity.class);
		
		startActivity(intent);
	}
	
}