Develop Reference

Android custom view set onClickListener with navigation

I've created a custom view that should be a button, but i can't quite get it to work.
So my custom view is extended from View, and I need to to make a fragment navigation when clicked
I've tried to use the override fun performClick() and in it do a rootView.findNavController().navigate(R.id.action_menu_to_settings) but it crashes. I also tried use the .setOnClickLister() { // navigation } but it also doesn't work.
Can anyone tell me how set a clickListener on a custom view for a navigation? Thx

If you are creating a custom view, the best way to handle the click operations is like this:
class MyView #JvmOverloads constructor (
context: Context,
attrs: AttributeSet? = null,
defStyleRes: Int = 0,
defStyleAttr: Int = 0
) : View(context, attrs, defStyleRes, defStyleAttr) {
var touchType = -1 // No user touch yet.
var onClickListener: () -> Unit = {
Log.d(TAG, "on click not yet implemented")
}
override fun onDraw(canvas: Canvas?) {
/* your code here */
}
override fun onTouchEvent(e: MotionEvent?): Boolean {
val value = super.onTouchEvent(e)
when(e?.action) {
MotionEvent.ACTION_DOWN -> {
/* Determine where the user has touched on the screen. */
touchType = 1 // for eg.
return true
}
MotionEvent.ACTION_UP -> {
/* Now that user has lifted his finger. . . */
when (touchType) {
1 -> onClickListener()
}
}
}
return value
}
}
And in your client class (Activity/Fragment), with the instance of the specific custom view that you instantiated, apply the following:
myView.onClickListener = {
findNavController().navigate(R.id.action_menu_to_settings)
}

How to make error message in TextInputLayout appear in center

Currently it looks as in attached with this layout:
<android.support.design.widget.TextInputLayout
android:id="#+id/layoutCurrentPW"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
app:errorEnabled="true">
How to set the error message "password must at least be 8 characters" to center gravity ?
I tried with android:gravity="center" but that did not work.
EDIT
Layout that includes EditText:
<android.support.design.widget.TextInputLayout
android:id="#+id/layoutCurrentPW"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
app:errorEnabled="true">
<EditText
android:id="#+id/editTextCurrentPassword"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:layout_marginLeft="50dp"
android:layout_marginRight="50dp"
android:gravity="center"
android:hint="#string/current_password"
android:inputType="textPassword"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#color/black" />
</android.support.design.widget.TextInputLayout>

I wanted to know if there is any way to handle it from framework..seems no.
But the way TextInputLayout work is:
- hint will be shown on top of EditText when user touches it.
- Error messages will be shown just under the TextInputLayout and aligned to start.
I had 40dp of left_margin to my EditText due to which misalignment between hint and error message. So for now, I removed left_margin 40dp from EditText and applied same to TextInputLayout itself so it looks fine now.
Lesson learnt :-) is if any margins has to be applied to EditText, better same, if possible, can be applied to TextInputLayout to keep hint and error messages to be placed properly.

class CenterErrorTextInputLayout(context: Context, attrs: AttributeSet) : TextInputLayout(context, attrs) {
override fun setErrorTextAppearance(resId: Int) {
super.setErrorTextAppearance(resId)
val errorTextView = this.findViewById<TextView>(R.id.textinput_error)
val errorFrameLayout = errorTextView.parent as FrameLayout
errorTextView.gravity = Gravity.CENTER
errorFrameLayout.layoutParams = LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT)
}}

Here a solution that always centers the errormessage no matter how big your TextInputLayout is.
You make a own class that inherits from TextInputLayout. Then override the ShowError(string text, Drawable icon) method. If the error is called you center the textView with the error.
public class TextInputLayout_Center : TextInputLayout
{
public override void ShowError(string text, Android.Graphics.Drawables.Drawable icon)
{
base.ShowError(text, icon);
centerErrorMessage(this);
}
void centerErrorMessage(ViewGroup view)
{
for (int i = 0; i < view.ChildCount; i++)
{
View v = view.GetChildAt(i);
if (v.GetType() == typeof(TextView))
{
v.LayoutParameters = new LayoutParams(ViewGroup.LayoutParams.MatchParent, v.LayoutParameters.Height);
((TextView)v).Gravity = GravityFlags.CenterHorizontal;
((TextView)v).TextAlignment = TextAlignment.Center;
}
if (v is ViewGroup)
{
centerErrorMessage((ViewGroup)v);
}
}
}
}

I achieved it by setting start margin for the error view. Below you can see my overriden version of setError method of the TextInputLayout component.
#Override
public void setError(#Nullable CharSequence errorText) {
// allow android component to create error view
if (errorText == null) {
return;
}
super.setError(errorText);
// find this error view and calculate start margin to make it look like centered
final TextView errorTextInput = (TextView) findViewById(R.id.textinput_error);
errorTextInput.measure(0, 0);
int errorWidth = errorTextInput.getMeasuredWidth();
int layoutWidth = getWidth();
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) errorTextInput.getLayoutParams();
params.setMarginStart((layoutWidth - errorWidth) / 2);
errorTextInput.setLayoutParams(params);
}

#Override
public void setErrorEnabled(boolean enabled) {
super.setErrorEnabled(enabled);
if (!enabled)
return;
try {
setErrorGravity(this);
} catch (Exception e) {
e.printStackTrace();
}
}
private void setErrorGravity(ViewGroup view) throws Exception {
for (int i = 0; i < view.getChildCount(); i++) {
View errorView = view.getChildAt(i);
if (errorView instanceof TextView) {
if (errorView.getId() == com.google.android.material.R.id.textinput_error) {
FrameLayout errorViewParent = (FrameLayout) errorView.getParent();
errorViewParent.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT));
((TextView) errorView).setGravity(Gravity.RIGHT);
((TextView) errorView).setTypeface(FontUtils.getTypeFace(view.getContext(), FontUtils.FONT_NAZANIN_TAR));
}
}
if (errorView instanceof ViewGroup) {
setErrorGravity((ViewGroup) errorView);
}
}
}

Hi if you using last version of material design (v 1.2 and above), you have to use this way: (I set gravity to end for support rtl)
Thanks #Emmanuel Guerra
class MyTextInputLayout : TextInputLayout {
constructor(context: Context) : super(context)
constructor(context: Context, attrs: AttributeSet?) : super(context, attrs)
constructor(context: Context, attrs: AttributeSet?, defStyleAttrs: Int) : super(context, attrs, defStyleAttrs)
override fun setErrorEnabled(enabled: Boolean) {
super.setErrorEnabled(enabled)
if (!enabled) {
return
}
try {
changeTextAlignment(com.google.android.material.R.id.textinput_error, View.TEXT_ALIGNMENT_VIEW_END)
val errorView: ViewGroup = this.getChildAt(1) as LinearLayout
val params: LinearLayout.LayoutParams = errorView.layoutParams as LinearLayout.LayoutParams
params.gravity = Gravity.END
errorView.layoutParams = params
//errorView.setPadding(0, 0, 0, 0) //use this to remove error text padding
//setErrorIconDrawable(0)
} catch (e: Exception) {
e.printStackTrace()
}
}
private fun changeTextAlignment(textViewId: Int, alignment: Int) {
val textView = findViewById<TextView>(textViewId)
textView.textAlignment = alignment
}
}

A custom TextInputLayout class for for aligning the error text.
class CenterErrorTextInputLayout #JvmOverloads constructor(
context: Context,
attrs: AttributeSet? = null,
defStyleAttr: Int = 0
) : TextInputLayout(context, attrs, defStyleAttr) {
override fun setErrorEnabled(enabled: Boolean) {
super.setErrorEnabled(enabled)
if (!enabled) return
try {
setErrorTextAlignment()
} catch (e: Exception) {
Timber.e(e, "Failed to set error text : RightErrorTextInputLayout")
}
}
private fun setErrorTextAlignment() {
val errorView: TextView = this.findViewById(R.id.textinput_error)
errorView.textAlignment = View.TEXT_ALIGNMENT_CENTER
}
}
To align the text to the end, use View.TEXT_ALIGNMENT_VIEW_END instead.

make editText lose focus on back press

In my activity, I have a editText field. When the user taps on it, the editText gains the focus and the keyboard appears. Now, when the user presses the hardware back button on the phone, the keyboard disappears but the cursor remains in the Edittext, i. e., it still has the focus. Is it possible to make the EditText lose focus when back button is pressed? I tried using the following code but it didn't work:
#Override
public void onBackPressed() {
vibrator.vibrate(Constants.DEFAULT_VIBRATE_TIME);
myEditText.clearFocus();
super.onBackPressed();
}

Just extend EditText:
public class EditTextV2 extends EditText
{
public EditTextV2( Context context )
{
super( context );
}
public EditTextV2( Context context, AttributeSet attribute_set )
{
super( context, attribute_set );
}
public EditTextV2( Context context, AttributeSet attribute_set, int def_style_attribute )
{
super( context, attribute_set, def_style_attribute );
}
#Override
public boolean onKeyPreIme( int key_code, KeyEvent event )
{
if ( key_code == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_UP )
this.clearFocus();
return super.onKeyPreIme( key_code, event );
}
}
And in the xml just use <yourPackage.EditTextV2> instead of <EditText>.
Note: You may need to add/remove constructors to this class depending on the min API you're supporting. I suggest just adding them all and removing the ones whose super() calls get underlined in red.

For anyone using Kotlin and Material Design, you can use this:
class ClearFocusEditText: TextInputEditText {
constructor(context: Context) : super(context)
constructor(context: Context, attrs: AttributeSet) : super(context, attrs)
constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int) : super(context, attrs, defStyleAttr)
override fun onKeyPreIme(keyCode: Int, event: KeyEvent?): Boolean {
if(keyCode == KeyEvent.KEYCODE_BACK) {
clearFocus()
}
return super.onKeyPreIme(keyCode, event)
}
}

You can make another of your Views focusable, for example an ImageView. Be sure to make it focusable in touch mode, using setFocusableInTouchMode(true) and on onResume() make that View to requestFocus().
Also you can create a dummy View with 0 dimensions and perform same steps described above.
I hope this helps.

Add view like the following higher than your EditText:
<LinearLayout
android:layout_width="0px"
android:layout_height="0px"
android:focusable="true"
android:focusableInTouchMode="true" />
Also to hide keyboard add this in onBackPressed():
((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(myEditText.getWindowToken(), 0);

I am providing kotlin equivalent code to Kacy answer with some edit
class CustomSearch #JvmOverloads constructor(context: Context, attrs: AttributeSet? =
null, defStyle: Int = 0):AppCompatEditText(context, attrs, defStyle) {
override fun onKeyPreIme(keyCode: Int, event: KeyEvent?): Boolean {
if (keyCode == KeyEvent.KEYCODE_BACK){
val imm:InputMethodManager = context.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
imm.hideSoftInputFromWindow(this.windowToken, 0)
this.clearFocus()
//this.findFocus()
}
return true
}
Note: I am returning true and this is solving my problem i.e removing focus from edit text and hiding soft input

This may be a possible solution:
EditText et;
et.setOnKeyListener(new View.OnKeyListener() {
#Override
public boolean onKey(View view, int i, KeyEvent keyEvent) {
if(i == KeyEvent.KEYCODE_BACK) {
et.clearFocus();
return true;
}
else return false;
}
});

Android Progress Bar Listener

Is there anyway to know when a progressbar has reached it maximum. Like a Listener then could plug into the ProgressBar and lets us know that the progress bar is at the maximum level ?
Kind Regards

There isn't a direct way to do this. A workaround could be to make a custom implementation of the ProgressBar and override the setProgress method:
public MyProgressBar extends ProgressBar
{
#Override
public void setProgress(int progress)
{
super.setProgress(progress);
if(progress == this.getMax())
{
//Do stuff when progress is max
}
}
}

I think the cleanest way would be just adding this to your code:
if (progressBar.getProgress() == progressBar.getMax()) {
// do stuff you need
}

If you need onProgressChanged like SeekBar - create custom progress (Kotlin):
class MyProgressBar : ProgressBar {
private var listener: OnMyProgressBarChangeListener? = null
fun setOnMyProgressBarChangeListener(l: OnMyProgressBarChangeListener) {
listener = l
}
constructor(context: Context?) : super(context)
constructor(context: Context?, attrs: AttributeSet?) : super(
context,
attrs
)
constructor(
context: Context?,
attrs: AttributeSet?,
defStyleAttr: Int
) : super(context, attrs, defStyleAttr)
override fun setProgress(progress: Int) {
super.setProgress(progress)
listener?.onProgressChanged(this)
}
interface OnMyProgressBarChangeListener {
fun onProgressChanged(myProgressBar: MyProgressBar?)
}
}
And for example in your fragment:
progress_bar?.setOnMyProgressBarChangeListener(object :
MyProgressBar.OnMyProgressBarChangeListener {
override fun onProgressChanged(myProgressBar: MyProgressBar?) {
val p = progress_bar.progress
// do stuff like this
if (p != 100) {
percentCallback?.changePercent(p.toString()) // show animation custom view with grow percents
} else {
shieldView.setFinishAndDrawCheckMark() // draw check mark
}
}
})

I think overall you should never have to do this. Is there just one valid case where you need to listen to a progressbar progress? I mean, usually it's the other way around: you set the progressbar progress based on something, not the other way around, so you need to track the progress of that something instead of listening to a view (which may or may not exist by the way).

Android PreferenceScreen title in two lines

I have PreferenceScreen with long title especially in some languages. I'm able to set multiple lines title for CheckBoxPreference or ListPreference with this:
Android preference summary . How to set 3 lines in summary? , but how to set 2-lines title for PreferenceScreen? I can change style like here: How can I change font size in PreferenceScreen but this doesn't look perfect and it's inconsistent with preference style (font, size ...).
thanks!

By default the title is set to single line.
You need to extend Preference and get title textview and set single line to false.
Use this class instead of the regular PreferenceScreen:
public class TwoLinePreference extends Preference {
public TwoLinePreference(Context ctx, AttributeSet attrs, int defStyle) {
super(ctx, attrs, defStyle);
}
public TwoLinePreference(Context ctx, AttributeSet attrs) {
super(ctx, attrs);
}
public TwoLinePreference(Context ctx) {
super(ctx);
}
#Override
protected void onBindView(View view) {
super.onBindView(view);
TextView textView = (TextView) view.findViewById(android.R.id.title);
if (textView != null) {
textView.setSingleLine(false);
}
}
}

Use the method setSingleLineTitle(false)
This was added in API 26, so you should be able to use the support library version for older devices

If you want just for a single preference, using setSingleLineTitle or app:singleLineTitle="false" in the XML file.
If you wish to apply it on all preferences, you can do it in multiple ways, when extending PreferenceFragmentCompat :
1.going over all preferences and setting it:
override fun setPreferenceScreen(preferenceScreen: PreferenceScreen?) {
if (preferenceScreen != null)
setAllPreferencesToHaveMultiLineTitles(preferenceScreen)
super.setPreferenceScreen(preferenceScreen)
}
private fun setAllPreferencesToHaveMultiLineTitles(preference: Preference) {
preference.isSingleLineTitle = false
if (preference is PreferenceGroup)
for (i in 0 until preference.preferenceCount)
setAllPreferencesToHaveMultiLineTitles(preference.getPreference(i))
}
2.Doing the same in the adapter, but not recommended as it might not work some day (reaches hidden API of the library) :
override fun onCreateAdapter(preferenceScreen: PreferenceScreen?): RecyclerView.Adapter<*> {
return object : PreferenceGroupAdapter(preferenceScreen) {
#SuppressLint("RestrictedApi")
override fun getItem(position: Int): Preference {
val item = super.getItem(position)
item.isSingleLineTitle = false
return item
}
}
}
3.Similar, but without using isSingleLineTitle (but again not recommended for the same reason) :
override fun onCreateAdapter(preferenceScreen: PreferenceScreen?): RecyclerView.Adapter<*> {
return object : PreferenceGroupAdapter(preferenceScreen) {
#SuppressLint("RestrictedApi")
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PreferenceViewHolder {
val holder = super.onCreateViewHolder(parent, viewType)
setPreferenceTitleTextViewToHaveMultipleLines(holder.itemView)
return holder
}
}
}
fun setPreferenceTitleTextViewToHaveMultipleLines(v: View) {
if (v is TextView && v.getId() == android.R.id.title)
return v.setSingleLine(false)
if (v is ViewGroup)
for (i in 0 until v.childCount)
setPreferenceTitleTextViewToHaveMultipleLines(v.getChildAt(i))
}

androidx.preferece library has no longer single line by default in title and summary.