相关疑难解决方法(0)

在android中如何在类文件中以编程方式设置导航抽屉头图像和名称？

在android studio 1.4.1中,我创建了默认的新导航抽屉项目.我的问题是在这个项目中有nav_header_main.xml文件,该文件用于导航标题图像和名称.我希望这个图像和名称应该在我的主类活动中以编程方式设置.怎么做,我尝试了很多,但应用程序崩溃了.

nav_header_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout        
android:layout_width="match_parent"
android:id="@+id/headerView"
android:layout_height="@dimen/nav_header_height"
android:background="@drawable/side_nav_bar"
android:gravity="bottom"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:theme="@style/ThemeOverlay.AppCompat.Dark">

<ImageView
    android:id="@+id/imageView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:paddingTop="@dimen/nav_header_vertical_spacing"
    android:src="@android:drawable/sym_def_app_icon" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:paddingTop="@dimen/nav_header_vertical_spacing"
    android:text="Android Studio"
    android:textAppearance="@style/TextAppearance.AppCompat.Body1" />

<TextView
    android:id="@+id/textView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="android.studio@android.com" />

</LinearLayout>

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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"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">

<include
    layout="@layout/app_bar_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<android.support.design.widget.NavigationView
    android:id="@+id/nav_view"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    android:fitsSystemWindows="true"
    app:headerLayout="@layout/nav_header_main"
    app:menu="@menu/activity_main_drawer" />

    </android.support.v4.widget.DrawerLayout>

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MainActivity.Class

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.NavigationView;
import android.support.design.widget.Snackbar;
import android.support.v4.view.GravityCompat; …

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android android-layout android-fragments androiddesignsupport android-navigationview

kal*_*lai

2015 11-06

71
推荐指数

8
解决办法

14万
查看次数

如何在导航抽屉标题中更改TextView的文本？

我想在导航抽屉标题内更改TextView的文本.但我得到这个错误:

java.lang.NullPointerException:尝试在空对象引用上调用虚方法'void android.widget.TextView.setText(java.lang.CharSequence)'

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"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <include
            layout="@layout/app_bar_main"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

        <FrameLayout
            android:id="@+id/frame_container"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />

    </LinearLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />

</android.support.v4.widget.DrawerLayout>

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nav_header_main

<?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="@dimen/nav_header_height"
    android:background="@drawable/slide_nav_bar"
    android:gravity="bottom"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:theme="@style/ThemeOverlay.AppCompat.Dark">

    <ImageView
        android:id="@+id/tvHeaderIcon"
        android:layout_width="60dp"
        android:layout_height="60dp"
        android:paddingTop="@dimen/nav_header_vertical_spacing"
        android:src="@android:drawable/sym_def_app_icon" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingTop="@dimen/nav_header_vertical_spacing"
        android:text="@string/app_name"
        android:textAppearance="@style/TextAppearance.AppCompat.Body1" />

    <TextView
        android:id="@+id/tvHeaderName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>

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MainActivity.java

TextView tvHeaderName; …

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java android textview

Sal*_*ari

2016 01-24

68
推荐指数

4
解决办法

6万
查看次数

将支持存储库更新到23.1.0后,在现有代码中出现错误

当我使用支持库23.0.0运行我的项目时,我没有收到任何错误,但今天当我将支持库更新到23.1.0时,我的活动代码在使用支持库的两个版本中完全相同.我收到以下错误:

10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime: FATAL EXCEPTION: main
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime: Process: com.galleri5.android, PID: 26271
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime: java.lang.IllegalArgumentException: Target must not be null.
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at com.squareup.picasso.RequestCreator.into(RequestCreator.java:618)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at com.squareup.picasso.RequestCreator.into(RequestCreator.java:601)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at com.galleri5.android.activities.HomeActivity$3.success(HomeActivity.java:155)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at com.galleri5.android.activities.HomeActivity$3.success(HomeActivity.java:151)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at retrofit.CallbackRunnable$1.run(CallbackRunnable.java:45)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135)
10-27 14:56:31.734 26271-26271/com.galleri5.android E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5254) …

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android android-support-library

Ami*_*ari

2015 10-29

2
推荐指数

1
解决办法

1304
查看次数