无法从微调菜单中获取任何颜色来改变颜色

Question

我试图让我的微调菜单通过更改任何颜色来响应。不能改变任何东西的颜色。选择绿色和之后请先查看图片。我正在学习如何为android编程。

这里是我的MainActivity.java

package com.romanescotech.mydropdownnavigation; 

import android.graphics.Color; 
import android.os.Bundle; 
import android.support.design.widget.FloatingActionButton; 
import android.support.design.widget.Snackbar; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.view.View; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.widget.AdapterView; 
import android.widget.ArrayAdapter; 
import android.widget.Spinner; 
import android.widget.SpinnerAdapter; 

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener { 

Spinner spinner; 
ArrayAdapter adapter; 
Toolbar toolbar; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    toolbar = (Toolbar) findViewById(R.id.toolbar); 
    setSupportActionBar(toolbar); 

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); 
    fab.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG) 
        .setAction("Action", null).show(); 
     } 
    }); 
    spinner = (Spinner) findViewById(R.id.spinnerMy); 
    adapter = ArrayAdapter.createFromResource(this, R.array.colors, R.layout.support_simple_spinner_dropdown_item); 
    adapter.setDropDownViewResource(R.layout.support_simple_spinner_dropdown_item); 
    spinner.setAdapter(adapter); 

} 

@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) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    int id = item.getItemId(); 

    //noinspection SimplifiableIfStatement 
    if (id == R.id.action_settings) { 
     return true; 
    } 

    return super.onOptionsItemSelected(item); 
} 
@Override 
public void onItemSelected(AdapterView<?> parent , View view, int pos, long id) { 
    parent.getItemAtPosition(pos); 
    String[] colors = getResources().getStringArray(R.array.colors); 
    String selectedColor = colors[pos]; 
    getWindow().getDecorView().setBackgroundColor(Color.parseColor(selectedColor)); 
    spinner.setBackgroundColor(Color.parseColor(selectedColor)); 
    view.setBackgroundColor(Color.parseColor(selectedColor)); 



} 
@Override 
public void onNothingSelected(AdapterView<?> parent) { 
// do nothing 
} 
} 

这里是我的activity_main.xml中

<?xml version="1.0" encoding="utf-8"?> 

<android.support.design.widget.AppBarLayout 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:theme="@style/AppTheme.AppBarOverlay"> 

    <android.support.v7.widget.Toolbar 
     android:id="@+id/toolbar" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:background="?attr/colorPrimary" 
     app:popupTheme="@style/AppTheme.PopupOverlay" /> 

    <Spinner 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:id="@+id/spinnerMy" 
     android:alpha=".8" /> 


</android.support.design.widget.AppBarLayout> 

<include layout="@layout/content_main" /> 

<android.support.design.widget.FloatingActionButton 
    android:id="@+id/fab" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_gravity="bottom|end" 
    android:layout_margin="@dimen/fab_margin" 
    app:srcCompat="@android:drawable/ic_dialog_email" /> 

这里是我的string.xml

<resources> 
<string name="app_name">MyDropDownNavigation</string> 
<string-array name="colors"> 
    <item>White</item> 
    <item>Red</item> 
    <item>Green</item> 
    <item>Blue</item> 
    <item>Yellow</item> 
</string-array> 
<string name="action_settings">Settings</string> 

这里是我的清单文件

<?xml version="1.0" encoding="utf-8"?> 

<application 
    android:allowBackup="true" 
    android:icon="@mipmap/ic_launcher" 
    android:label="@string/app_name" 
    android:supportsRtl="true" 
    android:theme="@style/AppTheme"> 
    <activity 
     android:name=".MainActivity" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme.NoActionBar"> 
     <intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 

      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
</application> 

这里是我的styles.xml

<resources> 

<!-- Base application theme. --> 
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"> 
    <!-- Customize your theme here. --> 
    <item name="colorPrimary">@color/colorPrimary</item> 
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item> 
    <item name="colorAccent">@color/colorAccent</item> 
</style> 

<style name="AppTheme.NoActionBar"> 
    <item name="windowActionBar">false</item> 
    <item name="windowNoTitle">true</item> 
</style> 

<style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" /> 

<style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" /> 

这里是我的其他V21 /款式XML

<resources> 

<style name="AppTheme.NoActionBar"> 
    <item name="windowActionBar">false</item> 
    <item name="windowNoTitle">true</item> 
    <item name="android:windowDrawsSystemBarBackgrounds">true</item> 
    <item name="android:statusBarColor">@android:color/transparent</item> 
</style> 

这里是它的照片做选择 before making selection

这里之前运行的是做选择后，manues ，背景一切都是相同的颜色。

after making selection

我猜我的问题就在于此方法。

public void onItemSelected(AdapterView<?> parent , View view, int pos, long id) { 
    parent.getItemAtPosition(pos); 
    String[] colors = getResources().getStringArray(R.array.colors); 
    String selectedColor = colors[pos]; 
    getWindow().getDecorView().setBackgroundColor(Color.parseColor(selectedColor)); 
    spinner.setBackgroundColor(Color.parseColor(selectedColor)); 
    view.setBackgroundColor(Color.parseColor(selectedColor)); 

在Java代码中

Answer 1

你的程序查找除了一个变化是正确的。 View发生更改后，您需要通知，以便视图了解发生的更改并将其反映到UI中。尝试在方法onItemSelected（）的末尾尝试调用adapter.notifydatasetchanged。

希望它可以帮助你。