我的项目有两项活动。 1）登录活动2）欢迎
首先，在实施任何登录验证之前，我试图从一个活动转移到另一个活动。我以前用了很多次。但对于这个项目，我无法找到我的应用程序在转换时停止的原因。
转换说明：当有人点击登录按钮时，会将他带到欢迎画面。 （实践中我没有实施任何认证）
的AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="world.yakuza.krishnavanshi.dev06_11_2015" >
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".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=".Launching"/>
<activity android:name=".SettingsActivity"
android:label="@string/title_activity_settings"
android:parentActivityName=".Launching" />
</application>
</manifest>
activity_main.xml中
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/navigation_drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="@bool/fitsSystemWindows">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="@dimen/status_bar_kitkat_height"
android:background="?colorPrimary"/>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="@dimen/status_bar_lollipop_height"
android:background="?colorPrimaryDark"/>
</LinearLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/status_bar_margin_top">
<TextView
android:id="@+id/txtusername"
android:layout_marginTop="32pt"
android:textSize="20dp"
android:textColor="@color/md_black_1000"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/Username" />
<EditText
android:layout_marginTop="45pt"
android:textSize="20dp"
android:textColor="@color/md_black_1000"
android:id="@+id/username"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/txtusername"
android:inputType="text" />
<TextView
android:id="@+id/txtpassword"
android:layout_marginTop="69pt"
android:textSize="20dp"
android:textColor="@color/md_black_1000"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/username"
android:text="@string/Password" />
<EditText
android:id="@+id/password"
android:layout_marginTop="85pt"
android:textSize="20dp"
android:textColor="@color/md_black_1000"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/txtpassword"
android:inputType="textPassword" />
<Button
android:id="@+id/login"
android:layout_marginTop="109pt"
android:textSize="20dp"
android:textColor="@color/md_white_1000"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/password"
android:text="@string/LoginBtn" />
<Button
android:id="@+id/signup"
android:layout_marginTop="130pt"
android:textSize="20dp"
android:textColor="@color/md_white_1000"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/login"
android:text="@string/SignupBtn" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?actionBarSize"
android:background="?attr/colorPrimary"
android:elevation="4dp"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
app:theme="@style/ToolbarTheme" />
</FrameLayout>
</android.support.v4.widget.DrawerLayout>
launching.xml（带导航标题和navigation_menu.xml的欢迎屏幕）
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/navigation_drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="@bool/fitsSystemWindows">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="@dimen/status_bar_kitkat_height"
android:background="?colorPrimary"/>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="@dimen/status_bar_lollipop_height"
android:background="?colorPrimaryDark"/>
</LinearLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/status_bar_margin_top">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Inbox"
android:textAppearance="@style/TextAppearance.AppCompat.Display1"
android:textColor="@color/md_text" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?actionBarSize"
android:background="?attr/colorPrimary"
android:elevation="4dp"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
app:theme="@style/ToolbarTheme" />
</FrameLayout>
<android.support.design.widget.NavigationView
android:id="@+id/navigation_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="@bool/fitsSystemWindows"
app:headerLayout="@layout/navigation_drawer_header"
app:menu="@menu/navigation_drawer_menu"
app:theme="@style/NavigationViewTheme" />
</android.support.v4.widget.DrawerLayout>
MainActivity.java
package world.yakuza.krishnavanshi.dev06_11_2015;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
Button login;
Toolbar toolbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
login = (Button) findViewById(R.id.login);
login.setOnClickListener(this);
}
@Override
public void onClick(View v) {
switch (v.getId()){
case R.id.login:
Intent intent = new Intent(getApplicationContext(),Launching.class);
startActivity(intent);
}
}
}
Launching.java
package world.yakuza.krishnavanshi.dev06_11_2015;
/**
* Created by Krishnavanshi on 06-11-2015.
*/
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.widget.Toast;
public class Launching extends AppCompatActivity {
DrawerLayout drawerLayout;
Toolbar toolbar;
ActionBar actionBar;
TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
actionBar = getSupportActionBar();
actionBar.setHomeAsUpIndicator(R.drawable.ic_menu_white_24dp);
actionBar.setDisplayHomeAsUpEnabled(true);
drawerLayout = (DrawerLayout) findViewById(R.id.navigation_drawer_layout);
NavigationView navigationView = (NavigationView) findViewById(R.id.navigation_view);
if (navigationView != null) {
setupNavigationDrawerContent(navigationView);
}
setupNavigationDrawerContent(navigationView);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
drawerLayout.openDrawer(GravityCompat.START);
return true;
}
return super.onOptionsItemSelected(item);
}
private void setupNavigationDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
textView = (TextView) findViewById(R.id.textView);
switch (menuItem.getItemId()) {
case R.id.item_navigation_drawer_about:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
drawerLayout.closeDrawer(GravityCompat.START);
return true;
case R.id.item_navigation_drawer_offers:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
drawerLayout.closeDrawer(GravityCompat.START);
return true;
case R.id.item_navigation_drawer_menu:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
drawerLayout.closeDrawer(GravityCompat.START);
return true;
case R.id.item_navigation_drawer_gallery:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
drawerLayout.closeDrawer(GravityCompat.START);
return true;
case R.id.item_navigation_drawer_booktable:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
drawerLayout.closeDrawer(GravityCompat.START);
return true;
case R.id.item_navigation_drawer_review:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
drawerLayout.closeDrawer(GravityCompat.START);
return true;
case R.id.item_navigation_drawer_settings:
menuItem.setChecked(true);
textView.setText(menuItem.getTitle());
Toast.makeText(Launching.this, "MainActivity " + menuItem.getTitle().toString(), Toast.LENGTH_SHORT).show();
drawerLayout.closeDrawer(GravityCompat.START);
Intent intent = new Intent(Launching.this, SettingsActivity.class);
startActivity(intent);
return true;
case R.id.item_navigation_drawer_help_and_feedback:
menuItem.setChecked(true);
Toast.makeText(Launching.this, menuItem.getTitle().toString(), Toast.LENGTH_SHORT).show();
drawerLayout.closeDrawer(GravityCompat.START);
return true;
}
return true;
}
});
}
}
的build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "23.0.1"
defaultConfig {
applicationId "world.yakuza.krishnavanshi.dev06_11_2015"
minSdkVersion 14
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:23.1.0'
compile 'com.android.support:design:23.1.0'
}
logcat的
11-06 12:09:42.480 0-934/? I/qemu-props﹕ connected to 'boot-properties' qemud service.
11-06 12:09:39.180 928-928/? W/auditd﹕ type=2000 audit(0.0:1): initialized
11-06 12:09:39.430 928-928/? I/auditd﹕ type=1403 audit(0.0:2): policy loaded auid=4294967295 ses=4294967295
11-06 12:09:39.430 928-928/? W/auditd﹕ type=1404 audit(0.0:3): enforcing=1 old_enforcing=0 auid=4294967295 ses=4294967295
11-06 12:09:42.480 0-934/? I/qemu-props﹕ receiving..
11-06 12:09:42.481 0-934/? I/qemu-props﹕ received: dalvik.vm.heapsize=64m
11-06 12:09:42.483 0-934/? I/qemu-props﹕ receiving..
11-06 12:09:42.483 0-934/? I/qemu-props﹕ received: qemu.sf.lcd_density=320
11-06 12:09:42.484 0-934/? I/qemu-props﹕ receiving..
11-06 12:09:42.485 0-934/? I/qemu-props﹕ received: qemu.hw.mainkeys=0
11-06 12:09:42.486 0-934/? I/qemu-props﹕ receiving..
11-06 12:09:42.486 0-934/? I/qemu-props﹕ received: qemu.sf.fake_camera=none
11-06 12:09:42.488 0-934/? I/qemu-props﹕ receiving..
11-06 12:09:42.488 0-934/? I/qemu-props﹕ received: ro.opengles.version=131072
11-06 12:09:42.504 0-934/? I/qemu-props﹕ receiving..
11-06 12:09:42.505 0-934/? I/qemu-props﹕ exiting (5 properties set).
11-06 12:09:42.666 0-945/? I/installd﹕ installd firing up
11-06 12:09:42.986 0-940/? I/Netd﹕ Netd 1.0 starting
11-06 12:09:43.042 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/default/optimistic_dad: No such file or directory
11-06 12:09:43.042 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/eth0/optimistic_dad: No such file or directory
11-06 12:09:43.043 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/lo/optimistic_dad: No such file or directory
11-06 12:09:43.043 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/sit0/optimistic_dad: No such file or directory
11-06 12:09:43.043 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/default/use_optimistic: No such file or directory
11-06 12:09:43.045 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/eth0/use_optimistic: No such file or directory
11-06 12:09:43.045 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/lo/use_optimistic: No such file or directory
11-06 12:09:43.046 0-940/? E/Netd﹕ Failed to open /proc/sys/net/ipv6/conf/sit0/use_optimistic: No such file or directory
--------- beginning of system
答案 0 :(得分：1)
您很可能为Launching活动设置了错误的布局：
setContentView(R.layout.activity_main);
它可能不是activity_main
答案 1 :(得分：1)
在Launching.java
替换此行
setContentView(R.layout.activity_main);
与
setContentView(R.layout.launching);
答案 2 :(得分：1)
使用
设置错误的布局 setContentView(R.layout.activity_main)
取代
setContentView(R.layout.launching)
这样活动就无法获得布局的ID，因此它会崩溃