re-setting a TextView height programmatically

问题

I want to reset a textView height after I have added it to the main window in the xml file.

inside a RelativeLayout,

  <TextView
      android:id="@+id/text_l"
      android:layout_width="50sp"
      android:layout_height="50sp"
      android:layout_alignParentTop="true"
      android:layout_centerHorizontal="true"
      android:layout_marginLeft="10sp"
      android:layout_marginTop="145dp"
      android:gravity="center"
      android:textAppearance="?android:attr/textAppearanceLarge"
      android:textColor="#000000" >
  </TextView>

I just want to change it from 50 to 70:

I tried:

 TextView text = (TextView)findViewById(R.id.text_l);
 text.setHeight(70);

but nothing changed.

回答1:

You should change it via LayoutParams:

LayoutParams params = (LayoutParams) textView.getLayoutParams();
params.height = 70;
textView.setLayoutParams(params);

EDIT

You should not use sizes in pixels in you code, use dimensions for this:

dimens.xml:

<dimen name="text_view_height">50dp</dimen>

In code:

params.height = getResources().getDimensionPixelSize(R.dimen.text_view_height);

回答2:

Pragmatically you can set textview height like:

private TextView mTxtView;
int height = 50; //your textview height
mTxtView.getLayoutParams().height = height;

回答3:

you can dynamically set width and height of textview by

private TextView mTxtView;
private int screenWidth, screenHeight;
Display display = getWindowManager().getDefaultDisplay(); 
    screenWidth = display.getWidth();
    screenHeight = display.getHeight();


LayoutParams params = mTxtView.getLayoutParams();
    params.width = screenWidth-30;
    mTxtView.setLayoutParams(params);

回答4:

I know this is an old question, but for the sake of others who might find this, there are scenarios where you should call textView.requestLayout() after changing the layout parameters. While it my be fine to omit it if you are simply changing the layout parameters as a one time thing before the layout is drawn. In my case, I wanted to change the height parameter of a TextView based on a radio button selection using onCheckedChangedListener, but the TextView height would only update the first time it was drawn. Adding requestLayout() solved this problem.

TextView tv;
ViewGroup.LayoutParams params = tv.getLayoutParams();
params.height = ViewGroup.LayoutParams.WRAP_CONTENT;
if(!tv.isInLayout()) {//make sure it isn't currently in a layout pass 
    tv.requestLayout();//request a layout pass
 }

回答5:

In Kotlin with DP to pixels translation

  changeTextHeight.setOnClickListener { view ->

         // random height for testing
        val randomHeightInDP = Random().nextFloat() * (50.0f - 10.0f) + 10

        // set Height in pixels
        hello.layoutParams.height = convertDpToPixel(randomHeightInDP, applicationContext)
         //refresh layout
        hello.requestLayout()


    }

Convert DP to pixels, see this post:

fun convertDpToPixel(dp: Float, context: Context): Int {
        return (dp * (context.resources.displayMetrics.densityDpi.toFloat() / DisplayMetrics.DENSITY_DEFAULT)).toInt()
    }

回答6:

the sample way for this if you want to use dimen

first, you should set size in dimen XML file.

<dimen name="text_height">50dp</dimen>
<dimen name="text_width">50dp</dimen>

and

text_l.getLayoutParams().height = 
     getResources().getDimensionPixelSize(R.dimen.text_height);

text_l.getLayoutParams().width = 
     getResources().getDimensionPixelSize(R.dimen.text_width);

if you want to set just int (for example we wanna set 50dp height and 100dp width)

text_l.getLayoutParams().height = 50 * 3;
text_l.getLayoutParams().width= 100 * 3;

来源：https://stackoverflow.com/questions/9175391/re-setting-a-textview-height-programmatically

标签

android

android-xml

textview