XML layout view not the same as emulator view

Question

Currently learning on how to build an android app, my xml file should show the text Sup doge in the layout preview but its not showing at all.

Here's the pic:

However, the text will show when I build the app & run it on an emulator:

Now I have a problem where I need to constantly build the app just to see any small UI changes in the emulator when I'm supposed to view it in the layout instead.

UPDATE #1:

I tried Invalidate Cache & Restart which was suggested by @Khemraj & removed the constraint attributes. Also removed the tools:text="@string/app_name" part but its still showing blank in the layout preview. It still shows fine when building the app.

Update #2:

Added background color to check. The preview has a problem.

Update #3

Here are gradle folder files:

gradle-wrapper.properties file

bulid.gradle file

HeadFirstProject01 file Anyone can help me fix this problem?

Solution:

Thanks to Khenraj's answer, I was using an unstable sdk ver so I had to update it to the previous stable ver & then build & sync gradle again:

    android {
        compileSdkVersion 27 //previously was 28
        defaultConfig {
            applicationId "com.example.headfirstproject_01.headfirstproject_01"
            minSdkVersion 14
            targetSdkVersion 27 //previously was 28
            versionCode 1
            versionName "1.0"
            testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        }
        buildTypes {
            release {
                minifyEnabled false
                proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
            }
        }
    }

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:27.1.1' //previously was 28.0.0-rc02
    implementation 'com.android.support.constraint:constraint-layout:1.1.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

you need to change the `app_name` string in the strings folder (I think the issue is at `tools:text =@string/app_name"` — , Aug 31 '18 at 07:54
Try adding background on TextView, problem is preview is not working at all. — Khemraj Sharma, Aug 31 '18 at 07:55
https://www.google.co.in/search?q=cant+see+layout+preview+androd&oq=cant+see+layout+preview+androd&aqs=chrome..69i57.7711j0j7&sourceid=chrome&ie=UTF-8 — Khemraj Sharma, Aug 31 '18 at 07:56
use the attribute **android:layout_alignParentLeft="true"** also as the error is showing on your xml file — Deepak Kumar, Aug 31 '18 at 07:56
See https://stackoverflow.com/questions/51591251/android-studio-textview-not-showing-in-design-view-layout/51591502#51591502 — Manohar, Aug 31 '18 at 08:19

Khemraj Sharma · Accepted Answer · 2018-08-31T09:01:32.660

1

The layout preview is not working. Use Invalidate Cache & Restart to see preview.

Suggestion:

RelativeLayout does not support constraint attributes. So remove those redundant constraint attributes from TextView.

Update

I seen many questions related this on SO. and answer is not one for all guys.

Here are few solutions:

Downgrade your sdk version. (compileSdkVersion, targetSdkVersion & support library versions)
Force refresh layout
Restart Android Studio

edited Aug 31 '18 at 09:01

answered Aug 31 '18 at 07:57

Khemraj Sharma

57,232
27
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Did you try setting background on TextView, does that show on Preview? – Khemraj Sharma Aug 31 '18 at 08:17
check my edit, even tried `Invalidate Cache & Restart` once more – Joshua Rajandiran Aug 31 '18 at 08:22
Sure your preview screen is not working, can you post your build.gradle file? – Khemraj Sharma Aug 31 '18 at 08:23
added, took screenshots of other files as well just in case – Joshua Rajandiran Aug 31 '18 at 08:34
You should use stable version of 28, for now you can downgrade to version 27. See https://stackoverflow.com/a/50833835/6891563 – Khemraj Sharma Aug 31 '18 at 08:40
Ok it works now after downgrading to ver 27. Can you edit your answer so that I could accept it? – Joshua Rajandiran Aug 31 '18 at 08:59

score 0 · Answer 2 · answered Aug 31 '18 at 07:52

0

In you xml you are using

tools:text="@string/app_name"

tools:text is very useful when we design our layouts using the designer. What it does is very easy: act instead of android:text, but only in the designer's preview. This means that in your preview you'll see what you've specified in tools:text. This applies to everything starting with tools:. For example, you could also specify which layout the preview has to use to show a recyclerview's item. I guess that your app_name string is empty, and this is why you are not seeing anything in the preview.

answered Aug 31 '18 at 07:52

Gregorio Palamà

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he is also using `android:text="'` – AskNilesh Aug 31 '18 at 07:53
1

android:text will apply on the real device. if you use tools:text, it will override android:text in the designer's preview – Gregorio Palamà Aug 31 '18 at 07:55

XML layout view not the same as emulator view

2 Answers2