# The screen reads empty

Source: https://phonebox.dev/docs/troubleshooting/empty-screen

> Why an observation can list few or no elements, how to work from screenshots and coordinates instead, and what truncated means.



An observation lists the elements that Android's accessibility layer reports: views that you can act on or that carry text or a description. Most apps report their buttons, fields and labels this way. When an observation lists few elements, or none, while the screen clearly shows something, one of these is usually the reason.

## The app draws its own screen [#the-app-draws-its-own-screen]

Games, canvas drawings, maps, many video players and some apps built with cross-platform frameworks draw their content themselves. Android then sees one large view with nothing inside it, so the observation lists little or nothing, and text, ID and description targets can't find anything.

Work from a screenshot and coordinates instead:

1. Observe with a screenshot, such as `GET /v1/phones/{id}/observe?screenshot=jpeg&max_width=720`, or `phonebox look --screenshot screen.jpg`.
2. Find what you want on the image, and convert the point to device pixels by dividing its coordinates by `screenshot.scale`. On a 1080-pixel-wide screen at `max_width=720`, the scale is 0.666667, so a point at (360, 800) on the image is (540, 1200) on the phone.
3. Tap, press or swipe at that point:

```json title="POST /v1/phones/{id}/actions"
{
  "actions": [
    { "type": "tap", "target": { "x": 540, "y": 1200 } },
    { "type": "wait", "ms": 1500 }
  ],
  "observe": "screenshot"
}
```

`"observe": "screenshot"` returns a new screenshot with the results, so you can check the effect of the tap without another request. When the screen couldn't be read, or not in time, the response has no `observation`, so observe before you go on. Since such an app offers nothing to wait for, a short `wait` gives it time to draw.

The [screenshot endpoint](/docs/api-reference/observe#take-a-screenshot) returns the image alone, with the screen's size and the scale in its headers, when you don't need the JSON.

## The app is still loading [#the-app-is-still-loading]

Right after an app opens, it may show a splash screen or a spinner with nothing to act on. Wait for what you expect, instead of observing again and again:

```json title="POST /v1/phones/{id}/actions"
{
  "actions": [
    { "type": "open_app", "package": "com.example.shop" },
    { "type": "wait_for", "target": { "text": "Search products" }, "timeout_ms": 20000 }
  ],
  "observe": "ui"
}
```

The same applies to a slow network inside an app. If the `wait_for` runs out with `wait_timeout`, the returned observation shows what is there instead. When the screen couldn't be read, or not in time, `observation` is missing, and you observe the screen yourself.

## The observation is truncated [#the-observation-is-truncated]

An observation lists at most 250 elements, in reading order from top to bottom. On a longer screen, `truncated` is `true`, and the text form ends with a line saying that more elements are on screen but not listed.

Text, ID and description targets search the same 250 elements, so an element beyond them can't be found by its label. Scroll until it moves up into the listed part, or scroll inside the list that holds it with a `scroll` action whose `target` is that list.

## Something covers the screen [#something-covers-the-screen]

* **The keyboard.** When `keyboard.visible` is `true`, the keyboard may hide elements at the bottom of the screen. Press `back` once to close it, or scroll.
* **A dialog or a permission prompt.** The observation shows the dialog's elements rather than the screen behind it. Answer the dialog first.
* **The wrong app.** The first line of the text form, `app …`, names the app in front. It reads `app unknown` when Phonebox couldn't tell which app it is. Open the app you meant with `open_app`.

## A web page [#a-web-page]

Browsers usually report a page's links, buttons and fields as elements. A page drawn on a canvas, or a web game, reports nothing, so use screenshots and coordinates as above.