如何使用菜单选项格式化来自其他活动的活动

Question

嗨,我是新手Android,我想从菜单选项更改活动的Textview大小和Textview颜色我不知道如何做到这一点

我创建了一个像这样的菜单项

<item android:id="@+id/menu_item_share"
    android:title="Share"
    android:showAsAction="ifRoom|withText"
    android:orderInCategory="100"
    app:actionProviderClass="android.support.v7.widget.ShareActionProvider" />

<item android:id="@+id/display"
    android:orderInCategory="100"
    android:showAsAction="ifRoom|withText"
    android:title="Display Option"
    android:actionLayout="@layout/custom_setting"  />

当我从当前布局菜单选项中单击显示选项时,需要调用新布局..在该布局中我创建了两个按钮,一个是加号按钮,另一个是减号按钮,我希望这些按钮对前一个布局进行更改.

当我单击加号按钮时,文本视图文本想要更改,当我单击减号按钮时,文本视图大小减少.

单击菜单项时的自定义布局代码

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context="com.example.aeiltech.sidd.CustomSetting" android:background="@mipmap/bg">

    <ImageButton
        android:layout_width="50dp"
        android:layout_height="40dp"
        android:background="@drawable/close"
        android:layout_above="@+id/textView"
        android:layout_toRightOf="@+id/minus"
        android:layout_toEndOf="@+id/minus"
        android:id="@+id/close" />

    <ImageButton
        android:layout_width="50dp"
        android:layout_height="40dp"
        android:background="@drawable/plusign"
        android:layout_marginTop="110dp"
        android:id="@+id/plus"
        android:layout_alignParentTop="true"
        android:layout_alignLeft="@+id/textView"
        android:layout_alignStart="@+id/textView" />

    <ImageButton
        android:layout_width="50dp"
        android:layout_height="40dp"
        android:background="@drawable/minusign"
        android:id="@+id/minus"
        android:layout_alignTop="@+id/plus"
        android:layout_alignRight="@+id/textView"
        android:layout_alignEnd="@+id/textView" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:text="Change Text Size"
        android:id="@+id/textView"
        android:layout_above="@+id/minus"
        android:layout_centerHorizontal="true"
        android:textColor="#FFFFFF" />

</RelativeLayout>

DetailActivity(此活动有Textview)

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.detail_activity);

    detailtext= (TextView) findViewById(R.id.detail);
    dbHelper = new SqlLiteDbHelper(this);

    try {
        dbHelper.openDataBase();
    } catch (SQLException e) {
        e.printStackTrace();
    }

    sqLiteDatabase = dbHelper.getReadableDatabase();
    cursor=dbHelper.getdetails(sqLiteDatabase, selectedData);

    if(cursor.moveToFirst())
    {
        detailtext.setText(cursor.getString(0));
    }

@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_detail, menu);
    MenuItem shareItem = menu.findItem(R.id.menu_item_share);
    mShareActionProvider = (ShareActionProvider) MenuItemCompat.getActionProvider(shareItem);

    return true;

}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if (id==R.id.display_option)
    {
        LayoutInflater layoutInflater= (LayoutInflater) getApplicationContext().getSystemService(LAYOUT_INFLATER_SERVICE);
        layoutInflater.inflate(R.layout.custom_setting,null);
    }

    return super.onOptionsItemSelected(item);
}

为了帮助澄清,这个问题与此应用程序和作者相同的应用程序崩溃当试图通过单击按钮更改textView中的文本大小时

Answer 1

以DialogFragment的形式显示新布局.我们的想法是以DialogFragment弹出窗口的形式显示增加/减少选项.你可以从弹出窗口增加/减少大小.弹出窗口解除后,所选大小将设置为Activity中的TextView.

MainActivity.java

public class MainActivity extends AppCompatActivity {

public static int updatedSize;
TextView greetingText;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    greetingText = (TextView)findViewById(R.id.hello_world_text);
}

@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) {
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        mycustomLayout();
        return true;
    }

    return super.onOptionsItemSelected(item);
}

public void mycustomLayout(){
    FragmentManager manager = getFragmentManager();
    PopUp popUp = new PopUp(new FragmentDismissHandler());
    popUp.show(manager,"POPUP");

}

public void refreshText(){
    if( updatedSize>0)
    greetingText.setTextSize(updatedSize);
}

private class FragmentDismissHandler extends Handler {
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        refreshText();
    }
}

}

activity_main.xml中

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

<TextView
    android:id="@+id/hello_world_text"
    android:text="@string/hello_world"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

PopUp.java(自定义布局为DialogFragment)

public class PopUp extends DialogFragment implements View.OnClickListener{

Button increase,decrease,set;
TextView sizeOfText;
static int size;
Handler handler;


public PopUp(Handler handler) {
    this.handler = handler;
}
public PopUp(){

}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    getDialog().setTitle("change text size");
    View view = inflater.inflate(R.layout.my_custom_layout, container, false);

    increase = (Button)view.findViewById(R.id.inc);
    increase.setOnClickListener(this);

    decrease = (Button)view.findViewById(R.id.dec);
    decrease.setOnClickListener(this);

    sizeOfText = (TextView)view.findViewById(R.id.size_text);
    sizeOfText.setText("text");

    set = (Button)view.findViewById(R.id.ok);
    set.setOnClickListener(this);

    size = (int) sizeOfText.getTextSize();

    return view;
}


@Override
public void onClick(View view) {
    int id= view.getId();

    if(id==R.id.inc){
        size = size +1;
        sizeOfText.setText("text");
        sizeOfText.setTextSize(size);
    }
    if(id== R.id.dec){
        size = size - 1;
        sizeOfText.setText("text");
        sizeOfText.setTextSize(size);
    }
    if(id== R.id.ok){
        dismiss();
    }
}

@Override
public void onDismiss(DialogInterface dialog) {
    super.onDismiss(dialog);
    MainActivity.updatedSize = size;
    handler.sendEmptyMessage(0);
}

}

my_custom_layout.xml

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

<Button
    android:id="@+id/inc"
    android:text="increase"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

    <Button
        android:id="@+id/dec"
        android:text="decrease"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    <TextView
        android:id="@+id/size_text"
        android:padding="20dp"
        android:textColor="@android:color/black"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/ok"
        android:text="set"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>