Listening for Page Size Changes, Dialog Obstruction Issues, Column Display Problems

[Daily HarmonyOS Next Knowledge] Listening for Page Size Changes, Dialog Obstruction Issues, Column Display Problems, Image Component Loading Issues, Routing Jumps

1. How to listen for real-time changes in NavPathStack size in HarmonyOS?

How to listen for real-time changes in NavPathStack size?

Current solutions in documentation: navDestinationUpdate has three issues:

1. Frequent updates trigger continuous callbacks.
2. Unnecessary in some scenarios (e.g., screen off or app backgrounding).
3. Inaccurate: No notification when pushing a new page changes the stack size.

Use observe.on instead. Reference: https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-arkui-observer-V5#ZH-CN_TOPIC_0000001930676413__observeronnavdestinationswitch12

2. HarmonyOS: Page blocked by pop-up dialog?

Steps to reproduce:

1. Click to pop up a dialog.
2. Navigate to a login page within the dialog, resulting in the page being blocked behind the dialog.

Solution: CustomDialog is a global pop-up with a high window hierarchy. Use window to lower the hierarchy.

API reference: https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-window-V5

3. HarmonyOS: When Navigation uses NavigationMode.Split, can bindSheet adapt to split-screen mode?

Half-modal behavior:

• When screen width < 600vp: Bottom pop-up.
• When screen width is in [600, 840): Centered pop-up.
• When screen width > 840vp: Default hand-following pop-up (appears below the bound sheet node).

4. HarmonyOS: Does setting visibility to Visibility.None on an Image component prevent the onComplete event from firing?

Issue: When visibility is set to Visibility.None, the onComplete event does not trigger.

Explanation: The onComplete interface returns the component's width and height (componentWidth and componentHeight), which require measurement to execute. If visible = false, the component is not measured, blocking the onComplete callback.

Solution: Keep visible = true by default. When an image fails to load, use the onError interface to set visible = false.

5. HarmonyOS: What is the difference between pushDestinationByName and pushPathByName?

• pushDestinationByName binds a context object and verifies context consistency during calls.
• pushPathByName does not verify context consistency.

Note: Different windows have different UIContexts. If used within the same window, they differ only in return values, with no other functional differences.