小编Roc*_*wer的帖子

我想在我的Android应用中显示全屏横幅.

在onCreate我称之为这个功能:

@Override 
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    showInterstitial();
}

我的功能:

private void showInterstitial() {

    interstitialAd = new InterstitialAd(this);
    interstitialAd.setAdUnitId(getString(R.string.ad_banner_id));
    interstitialAd.show();

    Toast.makeText(this, "Ad will load", Toast.LENGTH_SHORT).show();
}

我的应用程序将崩溃此消息:

引起:java.lang.IllegalStateException:必须在调用show之前在InterstitialAd上设置广告单元ID.

但是我在节目之前设置了广告ID,不是吗？

我想在ButterKnife中使用ViewStub,这就是我所做的:

public class ExampleFragment extends Fragment {

    @InjectView ( R.id.stub )
    ViewStub mStub;

    /* A TextView in the ViewStub */
    @InjectView ( R.id.text )
    @Optional
    TextView mText;

    @Override
    public View onCreateView ( LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState ) {

        View rootView = inflater.inflate ( R.layout.rootview, container, false );
        ButterKnife.inject ( this, rootView );

        mStub.setLayoutResource ( R.layout.stub_layout );
        View inflated = mStub.inflate ();
        ButterKnife.inject ( mStub, inflated );

        mText.setText("test.");    

        return rootView;
    }
}

并且日志说:

mText is a null object reference …

我正在尝试使用Android Studio编译项目，并且出现此错误。我已经将导入appcompat到build.gradle文件中：

dependencies {
    compile 'com.android.support:support-v4:21.0.+'
    compile 'com.android.support:appcompat-v7:21.0.+'
    compile 'com.melnykov:floatingactionbutton:1.1.0'
}

在几个文件中，我导入了这个文件：

import android.support.v7.app.ActionBarActivity;

这是一个使用gradle的Android应用程序.点击后Run,我找到了,但事件日志说:APP_V1.3.4_2016-02-22_11:30:29_google_play.apkoutputs/apk

11:30:31 EmptyThrowable:APK文件/.../WorkSpace/Android/.../app/build/outputs/apk/APP_V1.3.4_2016-02-22_ 11:30:14 _google_play.apk不存在在磁盘上.

11:30:32会话'app':安装APK时出错

这是我的build.gradle档案:

apply plugin: 'com.android.application'

def releaseTime() {
    return new Date().format("yyyy-MM-dd_HH:mm:ss",
        TimeZone.getTimeZone("GMT+08:00"))
}

android {
    compileSdkVersion 'Google Inc.:Google APIs:23'
    buildToolsVersion "23.0.2"

    defaultConfig {
        applicationId "com.example"
        minSdkVersion 14
        targetSdkVersion 23
        versionCode 29
        versionName "1.3.4"
        manifestPlaceholders = [SOME_CHANNEL_VALUE: "some_channel"]
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    signingConfigs {
        debug {}

        release {
            // ...
        }
    }

    buildTypes {
        debug {
            zipAlignEnabled true
            minifyEnabled false
            shrinkResources true
        }

        release {
            zipAlignEnabled true
            minifyEnabled true …

[
  {
    "id": "a",
    "pid": "a",
    "name": "AA",
  },
  {
    "id": "b",
    "pid": "a",
    "name": "BB",
  },
  {
    "id": "c",
    "pid": "a",
    "name": "CC",
  },
  {
    "id": "x",
    "pid": "b",
    "name": "XX",
  }
]

上面是我从数据库中获得的数据。每个人都有一个id和一个pid，pid指向该人的较高级别的人id。如果一个人的水平最高，则id等于pid。

我想将原始数据转换为分层JSON，如下所示：

[
  {
    "id": "a",
    "name": "AA",
    "child": [
      {
        "id": "b",
        "name": "BB"
        "child": [
          {
            "id": "x",
            "name": "XX"
          }
        ]
      },
      {
        "id": "c",
        "name": "CC"
      }
    ]  
  }
] …